Resin composition containing granular or powdery phenol-aldehyde resin

ABSTRACT

A resin composition comprising 
     (I) a granular or powdery resin which is a condensation product of a phenol, an aldehyde and optionally a nitrogen-containing compound having at least two active hydrogens and is characterized by (A) containing spherical primary particles and their secondary agglomerated particles each having a particle diameter of 0.1 to 150 microns, (B) having such a size that at least 50% by weight thereof can pass through a 100 Tyler mesh sieve, and (C) having a free phenol content, determined by liquid chromatography, of not more than 500 ppm, and 
     (II) at least one member selected from the group consisting of (1) a rubbery elastic material, (2) a thermoplastic resin and (3) a curable resin other than said granular or powdery resin (I) and/or a filler material other than said granular or powdery resin (I).

This is a division of application Ser. No. 619,833, filed June 12, 1984,now U.S. Pat. No. 4,558,089, which is a division of application Ser. No.452,737, Dec. 23, 1982 now U.S. Pat. No. 4,476,277.

This invention relates to a resin composition containing a novelgranular or powdery phenol-aldehyde resin, and more specifically, to aresin composition containing a novel granular or powdery phenol-aldehyderesin which has good storage stability and flow characteristics andreactivity and is suitable as a molding material.

Typical known phenol-aldehyde resins are novolak resins and resolresins.

The novolak resins are usually produced by reacting an excess of phenolwith formaldehyde in the presence of an acid catalyst such as oxalicacid (usually in an amount of 0.2 to 2%) while maintaining the moleratio of phenol to formaldehyde at, for example, 1:0.7-0.9. The novolakresins so produced have no self-crosslinkability and are thermoplasticbecause they are composed of, as main components, tri-, tetra- andpentamers resulting from the bonding of phenol moieties mainly bymethylene groups and contain almost no methylol groups. The novolakresins can be converted to cured resins by, for example, reacting themunder heat with a crosslinking agent, such as hexamine(hexamethylenetetramine), which is at once a formaldehyde generator andan organic base (catalyst) generator, or by mixing them with a solidacid catalyst and paraformaldehyde and reacting them under heat. Whensuch a novolak resin in accordance with the former method is used as amolding material, the resulting molded article will be foamed owing tothe generation of ammonia by the decomposition of hexamine, or theundecomposed part of hexamine or an organic base formed as a by-productwill remain in the molded article. This causes the defect that theproperties of the molded article are deteriorated, and the curingreaction is time-consuming. According to the latter curing method, thoseparts of the novolak resin which make contact with the paraformaldehydeand the acid catalyst undergo excessive crosslinking reaction, and it isdifficult to cure the resin uniformly. Furthermore, the acid catalyst orparaformaldehyde remains in the molded article to degrade its propertieswith the lapse of time, or troubles such as foaming occur owing to thedecomposition of the acid catalyst or paraformaldehyde during curing.Another defect is that since the novolak resin is obtained by thereaction of an excess of phenol and contains a relatively large amount(for example about 0.5 to about 2% by weight) of free phenol, a resincomposition containing it generates phenol when molded under heat andcauses troubles during the molding operation.

A process for producing cured novolak resin fibers was recentlysuggested which comprises heating a novolak resin at a high temperatureto form a product having a considerably high degree of condensation,purifying the product by removing components having a low degree ofcondensation thereby to obtain a product having a relatively high degreeof condensation and comprising phenol moieties linked to each other by 7to 10 methylene groups, melt-spinning the product to form novolakfibers, dipping the fibers in an aqueous solution of hydrochloric acidand formaldehyde and gradually heating the solution from roomtemperature to allow curing reaction to proceed from the surface of thefibers (Japanese Patent Publication No. 11284/1973). Granules or powdersobtained by cutting or pulverizing the cured fibers are expensive, anddo not possess good flow characteristics.

On the other hand, the known resol resins are produced usually byreacting phenol with an excess of formaldehyde in the presence of abasic catalyst (about 0.2 to 2% by weight based on the phenol) such assodium hydroxide, ammonia or an organic amine while maintaining the moleratio of phenol to formaldehyde at, for example, 1:1-2. The resol resinsso produced contain mono-, di- and trimers of phenol having a relativelylarge amount of methylol groups as main components and are veryreactive. It is the usual practice therefore to store them in arefrigerator as a water or methanol solution having a solidsconcentration of not more than 60%. The period for which such storage ispossible is about 3 to 4 months at the longest. To mold and cure such aresol resin, the water or methanol is removed and the resin is heated inthe optional presence of an acid catalyst. The rate of this curingreaction is very high, and, for example at 150° C., gellation occurswithin several tens of seconds. Since the resol resin has very highreactivity, it cannot be obtained as a stable granular or powdery solid.Furthermore, because a cured product of the resol resin has a highlydeveloped three-dimensional structure, it is very hard and itsconversion to a fine granular or powdery molding material is quitedifficult (Japanese Patent Publication No. 12958/1978). The resol resinsusually contain 1 to 10% by weight, based on the solids, of free phenol.

Several years ago, a process was disclosed which comprises reacting aphenol and formaldehyde in the presence of at least anitrogen-containing compound as a catalyst, and reacting the resultingcondensate with a hydrophilic polymeric compound to form a granular orpowdery resin (Japanese Patent Publication No. 42077/1978). Theresulting resin in the non-gelled state contains as much as about 5 to6% of free phenol (Examples 1 to 4 of the Japanese patent document), anda gelled product of the resin (Example 5 of the Japanese patentdocument) is a very hard non-reactive resin. Molded articles obtainedfrom the gelled resin have deteriorated properties because of itsinclusion of the nitrogen-containing compound used as catalyst or thehydrophilic polymeric compound.

A process is also known which comprises reacting a phenol andformaldehyde in a basic aqueous solution, mixing the resultingprepolymer with a protective colloid, and coagulating the prepolymerunder acidity to form inert solid beads (Japanese Patent Publication No.13491/1976). The coagulated product corresponds to a cured product of aresol resin, and has no reactivity. Furthermore, since it contains asalt or acid and the protective colloid, molded articles prepared fromit have degraded properties.

Attempts have been made to incorporate a phenol formaldehyde resin inthermoplastic resins, rubbers or curable resins, but from the viewpointof its use as a filler, it is first of all difficult to obtain it in ashape or form suitable as fillers. The phenol-formaldehyde resin alsohas the disadvantage that it contains substances which adversely affectthermoplastic resins, rubbers or curable resins.

The present inventors previously provided a novel granular or powderyphenol-aldehyde resin free from the aforesaid defects, and a process forits production.

It is an object of this invention to provide a resin compositioncontaining such a novel granular or powdery resin.

Another object of this invention is to provide a granular or powderyresin composition having good moldability which contains a granular orpowdery resin having good flow characteristics.

Still another object of this invention is to provide a resin compositionwhich contains a granular or powdery resin containing as small as notmore than 500 ppm of free phenol and is therefore safe and easy tohandle.

Yet another object of this invention is to provide a resin compositionwhich contains a granular or powdery resin capable of crosslinking withitself or with thermoplastic resins, rubbers or curable resins, and inwhich, therefore, the granular or powdery resin in the cured state canbe chemically combined with the thermoplastic resins, rubbers, etc. togive very uniform properties.

A further object of this invention is to provide a resin compositionwhich contains a granular or powdery nitrogen-containing resin and athermoplastic resin, and in the molded state, has excellent mechanicalproperties such as high strength, high hardness, low compression set andexcellent dimensional stability.

A still further object of this invention is to provide a resincomposition which contains a thermoplastic resin and gives moldedarticles having excellent electrical insulation or chemical resistanceand good platability.

A yet further object of this invention is to provide a resin compositioncontaining a rubbery elastic material, which contains a granular orpowdery resin having reactivity with the rubbery elastic material andtherefore in the cured state shows excellent mechanical properties suchas high strength, high hardness, low compression set, or excellentdimensional stability.

An additional object of this invention is to provide a resin compositionwhich contains a rubbery elastic material, and in the cured state, showsexcellent electrical insulation or heat resistance.

An additional object of this invention is to provide a resin compositionwhich contains a curable granular or powdery resin or a curable resin,is melted by heating, and in the cured state, has excellent wettabilitywith various fillers.

An additional object of this invention is to provide a resin compositionwhich contains a curable granular or powdery resin or a curable resin,and in the cured state, has excellent compression strength, chemicalresistance, electrical properties such as electric insulation, heatresistance or heat insulation, thus exhibiting the excellent propertiesof a phenol resin.

Other objects and advantages of this invention will become apparent fromthe following description and the accompanying drawings in which:

FIGS. 1 and 2 are each infrared absorption spectral charts by the KBrmethod of the granular or powdery resin obtained from phenol andformaldehyde obtained in Run No. 44 and from phenol, formaldehyde andurea obtained in Run No. 112, respectively.

In accordance with this invention,, these objects and advantages of thisinvention are achieved by a resin composition comprising

(I) a granular or powdery resin which is a condensation product of aphenol, an aldehyde and optionally a nitrogen-containing compound havingat least two active hydrogens and is characterized by (A) containingspherical primary particles and their secondary agglomerated particleseach having a particle diameter of 0.1 to 150 microns, (B) having such asize that at least 50% by weight thereof can pass through a 100 Tylermesh sieve, and (C) having a free phenol content, determined by liquidchromatography, of not more than 500 ppm, and

(II) at least one member selected from the group consisting of (1) arubbery elastic material, (2) a thermoplastic resin and (3) a curableresin other than said granular or powdery resin (I) and/or a fillermaterial other than said granular or powdery resin (I).

The granular or powdery phenol-aldehyde resin used in this invention isproduced from a phenol, an aldehyde and optionally a nitrogen-containingcompound having at least two hydrogens by a method to be describedhereinbelow.

The granular or powdery phenol-aldehyde resin (to be referred to as thegranular or powdery resin) is characterized by (A), (B) and (C) statedabove. The limitation that the spherical primary particles and theirsecondary agglomerated particles have a particle diameter of 0.1 to 150microns (A), the limitation that at least 50% by weight of the entireresin can pass through a 100 Tyler mesh sieve (B), and the limitationthat the resin has a free phenol content, determined by liquidchromatography, of not more than 500 ppm (C) are based on the measuringmethods to be described hereinbelow.

A first feature of the product of the invention is that it consistsmostly of spherical primary particles and secondary particles resultingfrom the agglomeration of the primary particles, each having a particlediameter of 0.1 to 150 microns, preferably 0.1 to 100 microns asspecified in (A) above and is quite different from a forcibly pulverizedproduct of a cured product of a known novolak or resol resin or apulverization product of known cured novolak fibers.

Usually at least 30%, preferably at least 50%, of the granular orpowdery resin consists of spherical primary particles and theiragglomerated secondary particles each of which has a particle diameterof 0.1 to 150 microns, preferably 0.1 to 100 microns.

In the case of the granular or powdery resin containing thenitrogen-containing compound, usually at least 30%, preferably at least50%, thereof consists of spherical primary particles and secondaryparticles resulting from the agglomeration of the primary particles,each of which has a particle diameter of 0.1 to 100 microns, preferably0.1 to 50 microns. The expression 30% or 50% means that as defined inthe description of the method for measuring the particle diameter givenhereinbelow, it is 30% or 50% based on the number of entire particles(including the secondary agglomerated particles) of the resin in onevisual field of an optical microscope having a magnification of 100 to1,000. It is preferred that 70% to substantially 100% of the granular orpowdery product consists of spherical primary particles and secondaryagglomerated particles each having a particle diameter of 0.1 to 150microns (0.1 to 100 microns in the case of the resin containing thenitrogen-containing compound). Especially preferably, at least 30%,especially at least 50%, of the number (as an average of those in fivevisual fields) of particles in the visual field of a microphotograph inaccordance with the above definition consists of spherical primaryparticles and secondary agglomerated particles having a particlediameter in the range of 0.1 to 100 microns, preferably 0.1 to 50microns (in the case of the resin containing the nitrogen-containingcompound, 0.1 to 50 microns, preferably 0.1 to 20 microns).

Since the granular or powdery resin product used in this invention isformed mainly of the minute spherical primary particles and thesecondary agglomerated particles thereof, it is very small in size asspecified in (B) above. Thus, at least 50% by weight, preferably atleast 70% by weight, especially preferably at least 80% by weight, ofthe entire resin passes through a 100 Tyler mesh sieve (a 150 Tyler meshsieve in the case of the resin containing the nitrogen-containingcompound). The expression "passing through the sieve" does not excludethe exertion of a force which does not cause forcible destruction of theparticles (including the secondary agglomerated particles) in theprocedure of screening the granular or powdery product through thesieve, for example light crumpling of the granular or powdery product byhand, light pushing or levelling of the particles on the mesh by meansof a brush, or light tapping of the particles by hand because theparticles of the granular or powdery resin of this invention becomeagglomerated as their average particle size becomes smaller.

As specified in (C) above, the granular or powdery resin used in theinvention has a free phenol content, determined by liquidchromatography, of not more than 500 ppm. The preferred free phenolcontent is not more than 250 ppm, above all not more than 100 ppm, forthe resin containing the nitrogen-containing compound, and above 50 ppmbut not more than 400 ppm, especially above 50 ppm but not more than 300ppm. That the powdery or granular resin used in the invention has a verylow free phenol content is presumably because the process for itsproduction described hereinbelow comprises adding the phenol or thephenol and the nitrogen-containing compound or the diluted solutionthereof to the HCl-aldehyde bath to form a uniform solution at leastpartly, then forming very fine white suspended particles and developingthem into stable fine particles, and therefore, substantially all of thephenol added, especially the phenol which participates in the formationof the product of the invention, reacts with the aldehyde present inlarge excess. The granular or powdery products obtained by the methodsdisclosed in Japanese Patent Publication No. 42077/1978 cited above hasa free phenol content of as high as 0.3 to about 6% by weight. Incontrast, the free phenol content of the granular or powdery resin usedin the invention is quite small, and this fact is an important advantageof the process of the invention using granular or powdery resins of thiskind and is very surprising.

The granular or powdery resin used in this invention may also be definedby the ratio of the absorption intensity of an absorption peak assignedto the aromatic double bond to that of an absorption peak assigned tothe methylol group in its infrared absorption spectrum. The positions ofthe two peaks and their absorption intensities differ somewhat dependingupon the presence or absence of the nitrogen-containing compound.

The granular or powdery resin substantially free from thenitrogen-containing compound has a D₉₉₀₋₁₀₁₅ /D₁₆₀₀ ratio of from 0.2 to9.0 in its infrared absorption spectrum determined by a KBr tabletmethod, wherein D₁₆₀₀ represents the absorption intensity of anabsorption peak at 1600 cm⁻¹ (the peak assigned to benzene) andD₉₉₀₋₁₀₁₅ represents the highest absorption intensity of absorptionpeaks in the range of 990 to 1015 cm⁻¹ (the peaks assigned to themethylol groups). This resin further has a D₈₉₀ /D₁₆₀₀ ratio, whereinD₈₉₀ represents the absorption intensity of a peak at 890 cm⁻¹ (the peakassigned to a lone hydrogen atom on the benzene ring), of from 0.09 to1.0. Preferably, it has a D₉₉₀₋₁₀₁₅ /D₁₆₀₀ ratio of from 0.2 to 7.0,especially from 0.4 to 5.0, and a D₈₉₀ /D₁₆₀₀ ratio of from 0.1 to 0.9,especially from 0.12 to 0.8.

It is widely known with regard to phenol-formaldehyde resins that intheir infrared absorption spectra, the peak at 1600 cm⁻¹ shows anabsorption assigned to the benzene ring, the peaks at 990 to 1015 cm⁻¹show absorptions assigned to the methylol groups, and the peak at 890cm⁻¹ shows an absorption assigned to a lone hydrogen atom on the benzenering.

The granular or powdery resin containing the nitrogen-containingcompound has a D₉₆₀₋₁₀₂₀ /D₁₄₀₀₋₁₅₀₀ ratio of from 0.1 to 2.0 in itsinfrared absorption spectrum measured by a KBr tablet method, whereinD₁₄₅₀₋₁₅₀₀ represents the highest absorption intensity of absorptionpeaks in the range of 1450 to 1500 cm⁻¹ (the peaks assigned to thearomatic double bond) and D₉₆₀₋₁₀₂₀ represents the highest absorptionintensity of absorption peaks in the range of 960 to 1020 cm⁻¹ (thepeaks assigned to the methylol groups), and preferably further has aD₁₂₈₀₋₁₃₆₀ /D₁₄₅₀₋₁₅₀₀ ratio of 0.15 to 3.0 in the infrared absorptionspectrum, wherein D₁₂₈₀₋₁₃₆₀ represents the highest absorption intensityof absorption peaks in the range of 1280 to 1360 cm⁻¹ (the peaksassigned to the carbon-nitrogen bond).

Preferably, this resin has a D₉₆₀₋₁₀₂₀ /D₁₄₅₀₋₁₅₀₀ ratio of from 0.15 to0.6 and further a D₁₂₈₀₋₁₃₆₀ /D₁₄₅₀₋₁₅₀₀ ratio of from 0.2 to 2.0.Especially preferably it has a D₉₆₀₋₁₀₂₀ /D₁₄₅₀₋₁₅₀₀ ratio of from 0.2to 0.4, and further a D₁₂₈₀₋₁₃₆₀ /D₁₄₅₀₋₁₅₀₀ ratio of from 0.3 to 1.5.

The resin used in this invention further has such a characteristic inits infrared absorption spectrum determined by a KBr tablet method thatit has a D₁₅₈₀₋₁₆₅₀ /D₁₄₅₀₋₁₅₀₀ ratio of from 0.3 to 4.5, preferablyfrom 0.75 to 2.0, especially preferably from 1.0 to 1.5, whereinD₁₅₈₀₋₁₆₅₀ represents the highest absorption intensity of absorptionpeaks in the range of 1580 to 1650 cm⁻¹.

Generally, it is difficult to determine the assignment of variousfunctional groups of a substance having a three-dimensional crosslinkedstructure by an infrared absorption spectroscopic method because peaksin its infrared absorption spectral chart frequently shift greatly. Butfrom the infrared absorption spectra of the phenol-aldehyde resin andvarious nitrogen-containing compounds, it has been determined that inthe infrared absorption spectrum of the resin of this invention, theabsorption peaks at 960 to 1020 cm⁻¹ are assigned to the methylolgroups, the absorption peaks at 1280 to 1360 cm⁻¹ are assigned to thecarbon-nitrogen bond, and the absorption peaks at 1450 to 1500 cm⁻¹ areassigned to the aromatic double bond.

The definite assignment of the absorptions at 1580 to 1650 cm⁻¹ isdifficult. But since the D₁₅₈₀₋₁₆₅₀ /D₁₄₅₀₋₁₅₀₀ using the highestabsorption intensity of the peaks at 1580 to 1650 cm⁻¹ can clearlydistinguish from the same ratio in a nitrogen-free phenol-formaldehyderesin, these absorptions can be recognized as characteristic absorptionsfor identifying the granular or powdery resin containing thenitrogen-containing compound.

It is understood that the ratio of absorption intensities in theinfrared absorption spectrum of the product of this invention, forexample, D₉₉₀₋₁₀₁₅ /D₁₆₀₀ =0.2-9.0 or D₉₆₀₋₁₀₂₀ /D₁₄₅₀₋₁₅₀₀ =0.1-2.0which is one parameter for specifying the granular or powdery resin usedin the invention, is a value associated with its structure and showsthat this resin contains a considerable amount of the methylol groupsand the methylol group content can be adjusted within a certain range.

The preferred product of this invention having a D₉₉₀₋₁₀₅₀ /D₁₆₀₀ ratioof from 0.2 to 7.0, or a D₉₆₀₋₁₀₂₀ /D₁₄₅₀₋₁₅₀₀ ratio of from 0.15 to0.6, and above all a D₉₉₀₋₁₀₁₅ /D₁₆₀₀ ratio of from 0.4 to 5.0 or aD₉₆₀₋₁₀₂₀ /D₁₄₅₀₋₁₅₀₀ ratio of from 0.2 to 0.4 contain methylol groupsin a moderate degree of concentration and is stabler.

The fact that in its infrared absorption spectrum the granular orpowdery resin used in this invention has a D₈₉₀ /D₁₆₀₀ ratio of from0.09 to 1.0, preferably from 0.1 to 0.9, above all from 0.12 to 0.8,shows that in this resin, the reaction sites (the ortho- andpara-positions) of phenol molecules which participated in the reactionare moderately blocked by methylol groups.

Generally, one or both of the D₉₉₀₋₁₀₁₅ /D₁₆₀₀ ratio and the D₈₉₀ /D₁₆₀₀ratio of a cured product of a known resol resin are lower than those ofthe granular or powdery resin used in this invention. A cured product ofa known novolak resin cured with hexamine has a D₈₉₀ /D₁₅₀₀ ratio whichis generally lower than the lower limit of this ratio of the product ofthis invention.

It has been found by elemental analysis that the granular or powderyresin used in this invention which is substantially free from thenitrogen-containing compound is composed of carbon, hydrogen and oxygenand has the following composition.

C: 70 to 80% by weight

H: 5 to 7% by weight

O: 17 to 21% by weight

(Total 100% by weight)

It has also been found that many of the granular or powdery resins usedin this invention which contain the nitrogen-containing compound containat least 1% by weight, preferably 2 to 30% by weight of nitrogen.

The granular or powdery resin used in this invention can be obtainedeither as a resin whose curing reaction has not proceeded to a greatextent or as a resin whose curing reaction has proceeded to some extent,by the manufacturing process to be described hereinbelow. Accordingly,when the granular or powdery resin used in this invention is pressed at100° C. for 5 minutes in accordance with the heat fusibility test to bedescribed hereinbelow, at least a part of the resin fuses to form alumpy or plate-like mass (i), or the resin assumes the form of agranules or powder without substantial melting or melt-adhesion (ii).

Those granular or powdery resins used in this invention which haverelatively high heat fusibility as mentioned above shows a methanolsolubility, measured by the testing method to be given hereinbelow, ofat least 20% by weight, especially at least 30% by weight, and in somecases, at least 40% by weight.

Since the granular or powdery resin contains spherical primary particlesand their secondary agglomerated particles each having a particlediameter of 0.1 to 150 microns [the characteristic (A) describedhereinabove] in an amount of preferably at least 30%, and usually atleast 50% by weight, preferably at least 70% by weight, of the resinparticles can pass through a 100 Tyler mesh sieve, the resin has verygood flowability, and can be mixed with another material easily and in arelatively large amount. Furthermore, since many of the granular orpowdery resins used in this invention contain very minute sphericalprimary particles as a basic constituent, a cured molded articleprepared from a resin composition containing this resin has excellentmechanical properties, particularly high resistance to compression. Thegranular or powdery resins are very stable at ordinary temperatures andcontain considerable amounts of methylol groups. Hence, they showreactivity when heated, and give cured molded articles having not onlyexcellent physical and mechanical properties but also excellent thermalinsulation, heat resistance and electrical properties such as electricalinsulation, and chemical resistance.

Furthermore, the granular or powdery resin has a free phenol content ofusually not more than 500 ppm, and therefore, its handling is very easy,and safe. Furthermore, because of its very low free phenol content, aside-reaction attributed to the phenol is reduced in obtaining aprecursor article from the granular or powdery resin.

The granular or powdery resin does not substantially contain ahydrophilic polymeric compound because it is produced by a process inwhich the reaction system does not substantially contain a hydrophilicpolymeric compound.

The granular or powdery resin used in this invention is very fine andhas good storage stability and flow characteristics. Furthermore,because it contains a certain amount of methylol groups, it hasreactivity when molded into a precursor article and heated. Hence, itgives a cured article having uniform properties.

The granular or powdery resin used in this invention can be produced bycontacting a phenol, or both a phenol and a nitrogen-containing compoundcontaining at least two active hydrogens with a hydrochloricacid-aldehyde bath containing (a) hydrochloric acid (HCl) in aconcentration of 3 to 28% by weight, preferably 8 to 25% by weight,above all 12 to 22% by weight and (b) formaldehyde (HCHO) in aconcentration of 3 to 25% by weight, preferably 5 to 20% by weight,above all 7 to 15% by weight, and other aldehydes in a concentration of0 to 10% by weight with (c) the total concentration of hydrochloric acidand formaldehyde being 10 to 40% by weight, preferably 15 to 35% byweight, above all 20 to 32% by weight, while maintaining a bath ratio,defined by the quotient of the weight of the hydrochloric acid-aldehydebath divided by the total weight of the phenol and thenitrogen-containing compound, of at least 8.

Preferably, in addition to the three requirements (a), (b) and (c), thecomposition of the HCL-aldehyde bath is such that the mole ratio of thealdehyde in the bath to the phenol to be contacted with the bath or thephenol and the nitrogen-containing compounds combined is at least 2,especially at least 2.5, above all at least 3 [requirement (d)]. Thereis no particular upper limit to the above mole ratio (d). Preferably,the upper limit is 20, especially 15. The especially preferred moleratio (d) is from 4 to 15, above all from 8 to 10. The characteristicfeature of the aforesaid process is that a bath of an aqueous solutionof hydrochloric acid and formaldehyde having a considerably high HClconcentration and containing formaldehyde in molar excess to the phenolor both the phenol and the nitrogen-containing compound is contactedwith the phenol or both the phenol and the nitrogen-containing compoundat a bath ratio of at least 8, preferably at least 10.

Since the aforesaid process is carried out while the concentration ofeach of hydrochloric acid and aldehyde is kept at at least 3% by weight,and the bath ratio, at not less than 8, the weight percentage ofhydrochloric acid or aldehyde based on the weight of the phenol or thetotal weight of the phenol and the nitrogen-containing compound is atleast 24% by weight. Furthermore, since in this process, the totalconcentration of hydrochloric acid and formaldehyde is at least 10% byweight, the total weight of hydrochloric acid and aldehyde based on theweight of the phenol or the total weight of the phenol and thenitrogen-containing compound is at least 80% by weight. These reactionconditions are fundamentally different from the reaction conditions forthe production of known novolak and resol resins described hereinabove.

When the phenol or the phenol and the nitrogen-containing compound areto be contacted with the HCL aldehyde bath, the bath ratio (as definedhereinabove) is preferably at least 10, especially preferably 15 to 40.

In the aforesaid process, the phenol or the phenol and thenitrogen-containing compound are contacted with the HCl-formaldehydebath such that after contacting of the phenol with the bath, whitesuspended particles are formed and thereafter developed into a granularor powdery solid (preferably into a pink-colored granular or powderysolid when the nitrogen-containing compound is not used). The contactingof the phenol and the nitrogen-containing compound with the HCL-aldehydebath is conveniently carried out such that by adding the phenol and thenitrogen-containing compound together to the HCL-aldehyde bath or firstadding the nitrogen-containing compound and then the phenol to the bath,a clear solution is first formed and then white suspended particles areformed and thereafter developed into a granular or powdery solid. Incontacting the bath with the phenol or the phenol and thenitrogen-containing compound, it is preferred that before the whitesuspended particles are formed by the addition of the phenol, the bathbe stirred to form a clear, preferably uniform, solution of the phenolor the phenol and the nitrogen-containing compound, and that after theformation of the white suspended particles until the suspended particleschanges to a solid, the bath (reaction mixture) be not subjected to amechanical shearing force such as stirring depending upon the ratio ofthe phenol to the nitrogen-containing compound or the reactionconditions.

The phenol may be added as such, but if desired, it may be diluted withformalin, an aqueous solution of hydrochloric acid, water, etc. prior tothe addition.

The temperature of the HCL-aldehyde bath with or without thenitrogen-containing compound dissolved therein, to which the phenol orboth the phenol and the nitrogen-containing compound (or the dilutedsolution thereof) are to be added is suitably not more than 90° C.,preferably not more than 70° C. If the temperature of the bath is higherthan 40° C., especially higher than 50° C., the rate of the reaction ofthe phenol or the nitrogen-containing compound with aldehyde increases,it is preferred to add the phenol or both the phenol and thenitrogen-containing compound as a solution diluted with formalin.Furthermore, since the rate of the reaction is high, it is preferred toadd the phenol, or both the phenol and the nitrogen-containing compound,preferably a diluted solution thereof as fine streams or smallestpossible droplets to the bath.

When the phenol or both the phenol and the nitrogen-containing compoundare added to the bath having a temperature of more than 40° C.,especially more than 50° C., the rate of the reaction of the phenol andthe nitrogen-containing compound becomes higher as the temperature ofthe bath becomes higher. Thus, within several minutes or instantaneouslyafter the contacting, while suspended particles form and are rapidlydeveloped into a granular or powdery solid.

A granular or powdery solid obtained by adding the phenol or both thephenol and the nitrogen-containing compound, either as such or as adiluted solution thereof, preferably a water diluted solution thereof,to the HCl-aldehyde bath maintained at not more than 40° C., preferably5° to 35° C., especially preferably 10° to 30° C., and after theformation of white suspended particles, completing the desired reactionat not more than about 50° C., preferably not more than 45° C. showsheat fusibility in the 100° C. fusibility test to be described belowbecause its curing reaction has not proceeded to a great extent.

On the other hand, a granular or powdery solid obtained by addingsubstantially all of the phenol or the phenol and thenitrogen-containing compound or the diluted solution thereof to theHCL-aldehyde bath maintained at nor more than 45° C., preferably 15° to35° C. with stirring to form a clear solution, thereafter forming whitesuspended particles without stirring, then forming a granular or powderysolid with or without temperature elevation, and heating the solid at atemperature higher than 50° C., preferably 70° to 95° C., to completethe desired reaction has little or substantially no heat fusibility at100° C., or shows heat fusibility at a higher temperature, for exampleat 200° C., or has substantially no heat fusibility at such a hightemperature.

When both the phenol and the nitrogen-containing compound are used, itis possible in both of the above-described cases to first add thenitrogen-containing compound to the HCl-formaldehyde bath and then addthe phenol alone.

Phenol is most preferred as the phenol. The phenol may also be a mixtureof at least 50% by weight, preferably at least 70% by weight, of phenolwith at least one known phenol derivative such as o-cresol, m-cresol,p-cresol, bisphenol A, bisphenol S, o-, m- or p-(C₂ -C₄ alkyl)phenols,p-phenylphenol, xylenol, resorcinol and hydroquinone.

Suitable formaldehyde supply sources for the HCl-aldehyde bath includeformalin, trioxane, tetraoxane and paraformaldehyde.

The HCL-aldehyde bath used in this invention may include up to 10% byweight of an aldehyde other than formaldehyde in addition to theaforesaid formaldehyde supply sources. Examples of suitable otheraldehydes are monofunctional aliphatic aldehydes having 2 to 4 carbonatoms, glyoxal, furfural and benzaldehyde. Examples of themonofunctional aliphatic aldehydes include acetaldehyde,propionaldehyde, n-butyl aldehyde and iso-butyl aldehyde. Thesealdehydes may be used singly or as a mixture of two or more.

The nitrogen-containing compound used in this invention is a compoundcontaining at least two active hydrogens in the molecule. Preferably, itcontains in the molecule at least one group having active hydrogensselected from the class consisting of amino groups, amide groups,thioamide groups, ureylene groups and thioureylene groups. Examples ofsuch nitrogen-containing compound are urea, thiourea, methylolderivatives of urea or thiourea, aniline, melamine, guanidine,guanamine, dicyandiamide, fatty acid amides, polyamide, toluidine,cyanuric acid, and functional derivatives of these compounds. They maybe used either singly or as a mixture of two or more.

The granular or powdery resin solid formed in the bath as a result ofthe completion of the desired reaction is separated from theHCL-aldehyde bath, washed with water, preferably treated with an aqueousalkaline solution such as aqueous ammonia or a methanolic aqueousammonia solution to neutralize the adhering hydrochloric acid, and againwashed with water to give the desired product. As a matter of course, aresin having a relatively high solubility in methanol is preferablyneutralized with an aqueous alkaline solution.

The resin of this invention is characterized by containing the aforesaidfine granular or powdery phenol-aldehyde resin.

The resin composition of this invention is described below according tovarious embodiments.

Embodiments 1

The resin composition of this invention according to embodiment 1contains a thermoplastic resin in addition to the granular or powderyphenol-aldehyde resin described above.

A wide variety of thermoplastic resins known in the art of polymers canbe used in this invention. For example, there may be preferably usedversatile engineering plastics such as polyethylene resins,polypropylene resins, polystyrene resins, acrylic resins, vinyl resins,fluorine-containing resins, polyacetal resins, polyamide resins,polyester resins, polycarbonate resins, and polyurethan resins. Thepolyethylene resins, polypropylene resins, vinyl resins, polyamideresins and polyester resins are especially preferred. Thesethermoplastic resins may be used singly or as a mixture of two or more.

The aforesaid thermoplastic resins include both homopolymers andcopolymers, and the copolymers may be random, graft or block copolymers.The polyethylene resins contain preferably at least 50% by weight, morepreferably at least 85% by weight, of ethylene units in the polymerchain. The polypropylene resins contain preferably at least 50% byweight, more preferably at least 85% by weight, of propylene units inthe polymer chain. The polystyrene resins contain preferably at least50% by weight, more preferably at least 85% by weight, of styrene unitsin the polymer chain. The acrylic resins contain preferably at least 50%by weight, more preferably at least 85% by weight, of methyl or ethylacrylate or methacrylate units in the polymer chain.

The vinyl resins contain preferably at least 50% by weight, morepreferably at least 85% by weight, of units of a vinyl monomercontaining an ethylenically unsaturated bond such as vinyl chloride,vinylidene chlorice or vinyl acetate. Polyvinyl chlorice is especiallypreferred as the vinyl resin.

The fluorine-containing resins contain preferably at least 50% byweight, more preferably at least 85% by weight, of units of afluorine-containing vinyl monomer such as tetrafluoroethylene,fluoroethylene or hexafluoropropylene.

The polyethylene resins, polypropylene resins, poly-styrene resins,acrylic resins, vinyl resins and fluorine-containing resins may include,in addition to the aforesaid main units, other structural units whichare derived from such monomers as ethylene, propylene, acrylic acid,methacrylic acid, a lower alkyl (e.g., a methyl or ethyl) ester ofacrylic or methacrylic acid, styrene, α-methylstyrene, vinyl chloride,vinyl acetate and acrylonitrile.

Preferred polyacetal resins are, for example, polyoxymethylene andpoly(oxymethylene-oxyethylene)copolymer. Thepoly(oxymethylene-oxyethylene)copolymer may contain not more than 15% byweight of oxyethylene units derived from ethylene oxide in the polymerchain.

Examples of preferred polyamide resins include polycaproamide (6-nylon),polyhexamethylene adipamide (6,6-nylon), polyhexamethylene sebacamide(6,10-nylon), polyundecanamide (11-nylon), polydodecanamide (12-nylon),and polyundecamethylene terephthalamide (11,T-nylon).

The preferred polyester resins are unsaturated polyester resins, such aspolyethylene terephthalate, polytetramethylene terephthalate andpolyhexamethylene tere phthalate.

Preferably, the polycarbonate resins are polycarbonates of bisphenols,particularly bisphenol A.

The thermoplastic resins used in this invention are well known in theart.

Strictly, the suitable mixing ratio between the granular or powderyresin and the thermoplastic resin in the resin composition in accordancewith embodiment 1 differs depending upon the properties of the granularor powdery resin used, for example whether it is heat-fusible or not, orupon the type of the thermoplastic resin used.

For example, the resin composition of this invention contains 1 part byweight of the thermoplastic resin and 0.01 to 20 parts by weight,pareferably 0.02 to 3 parts, especially preferably 0.03 to 0.9 part, byweight, of the granular or powdery resin.

The resin composition of this invention is provided either as athermoplastic or thermosetting composition.

The present invention provides a particularly preferred resincomposition being thermoplastic and containing 1 part by weight of thethermoplastic resin and 0.05 to 0.5 part by weight of the granular orpowdery resin. A heat-setting thermosetting resin composition inaccordance with this invention is obtained generally when the granularor powdery resin has high reactivity and the amount of the thermoplasticresin is relatively small, or when the thermoplastic resin has highreactivity with the highly reactive granular or powdery resin althoughits amount is relatively large. Suitable proportions of the constituentresins which will give such a resin composition of this invention willbecome apparent from the following description.

As is seen from the foregoing description, the resin composition of thisinvention contains the powdery or granular or powdery phenol-aldehyderesin which when pressed at 100° C. for 5 minutes according to the heatfusibility test to be described hereinbelow, (i) is at least partlymelt-adhered to form a lumpy or plate-like product, or (ii) is in thegranular or powdery form with out substantial melting or melt-adhesion.It can be said that these species of the granular or powdery resin havethermosetting properties because they further undergo curing reactionupon reating. The difference is that the resin having the property (i)is melted or melt-adhered upon heating because its curing reaction hasnot yet proceeded fully, whereas the resin having the property (ii)remains granular or powdery without melting or melt-adhesion uponheating because its curing reaction has further proceeded as comparedwith the resin having the property (i).

The resin composition of this invention comprises the thermoplasticresin as the other component. Since the resin composition of theinvention thus contains both the thermosetting resin and thethermoplastic resin, it generally has a greater tendency to bethermoplastic when the content of the thermosetting resin is low and tobe thermosetting when the content of the thermosetting granular orpowdery resin is large.

However, whether the resin composition of this invention isthermoplastic or thermosetting does not simply depend upon the mixingratio of the granular or powdery resin and the thermoplastic resin.

Investigations of the present inventors have shown that a resincomposition in accordance with this invention which is thermoplastic canbe advantageously provided by the following embodiments.

(1) When the heat-fusible species (i) described above is used as thegranular or powdery nitrogen-containing resin, it is advantageous to usethe granular or powdery resin in an amount of not more than 0.5 part byweight per part by weight of the thermoplastic resin.

(2) When the species (ii) which does not melt or melt-adhere is used asthe granular or powdery resin, the amount of the granular or powderyresin is advantageously not more than 2 parts by weight per part byweight of the thermoplastic resin.

(3) When a mixture of the species (i) and (ii) is used as the granularor powdery resin, it is preferred to adjust its amount such that perpart by weight of the thermoplastic resin, the amount of the resinspecies (i) is not more than 0.5 part by weight and the total amount ofthe mixture is not more than 1.5 parts by weight.

The resin compositions in accordance with this invention which arethermoplastic can be molded by methods generally used for the molding ofthermoplastic resins, such as extrusion molding or molding in a die. Theresulting molded articles have better mechanical properties such ashigher strength, higher hardness, lower compression set, betterdimensional stability and higher heat deformation temperatures, orbetter electric insulation, chemical resistance, platability or heatresistance than molded articles prepared from the thermoplastic resinused.

Investigations of the present inventors have also shown that a resincomposition in accordance with this invention which is thermosetting canbe advantageously provided by the following embodiments.

(1) When the species (i) is used as the granular or powdery resin, itsamount is preferably more than 0.5 part by weight, more preferably atleast 0.6 part by weight, per part by weight of the thermoplastic resin.

(2) When the species (ii) is used as the granular or powdery resin, itsproportion is preferably more than 2 parts by weight but does not exceed6 parts by weight, more preferably more than 2 parts by weight but doesnot exceed 3 parts by weight, per part by weight of the thermoplasticresin. As the thermoplastic resin, there can be used those thermoplasticresins which have reactivity with the granular or powdery resin, such aspolyamides, polyvinyl chloride and polyacetal resins. If the granular orpowdery resin is used in amounts exceeding the aforesaid upper limits,it is difficult to obtain a molded article from the resulting resincomposition.

(3) When a mixture of the species (i) and (ii) is used as the granularor powdery resin, it is advantageous to adjust its amount such that perpart by weight of the thermoplastic resin, the total amount of themixture is more than 0.5 part by weight, but does not exceed 20 parts byweight, and the amount, x, of the resin species (i) and the amount, y,of the resin species (ii) satisfy the expression 6-0.3x>y>2-4x.

The resin compositions of this invention which are thermosetting can bemolded by methods generally used for the molding of thermosettingresins, for example by molding in a die. The resulting molded articleshave higher toughness, strength and hardness, lower compression set,better dimensional stability, electrical insulation, chemicalresistance, heat resistance and platability than those obtained from thegranular or powdery resin alone.

As required, the resin composition of this invention may contain variousfillers, for example fibrous materials such as glass fibers, carbonfibers or rock wool; granular or powdery materials such as carbon,silica, talc, alumina, silica-alumina, diatomaceous earth, calciumcarbonate, calcium silicate, magnesium oxide, clay, antimony oxide,hollow microspheres, or powders of metals such as iron, nickel andcopper; or organic materials such as wood flour, linter, pulp orpolyamide fibers. These fillers may be included in an amount of not morethan 30% by weight, preferably not more than 20% by weight, based on thetotal weight of the resin composition.

The resin composition of this invention which is thermoplastic can beproduced by introducing the granular or powdery phenol-aldehyde resin,the thermoplastic resin and optionally fillers into a melt extrudereither as such or after mixing them in the solid state in a mixer suchas a V-type blender, and melt-mixing them in the melt extruder. Theresin composition of this invention can be obtained there either aschips or pellets, or as a molded article.

It is also possible to feed a solid mixture of the aforesaid componentsof the resin composition of this invention which is thermoplastic or theaforesaid chips or pellets into a mold or an injection molding machine,and convert such a material into a molded article by molding in the moldor by injection molding.

The resin composition of this invention which is thermosetting may beconverted to a molded article usually by feeding a solid mixture of itscomponents in a mixer such as a V-type blender into a mold and moldingit there. If desired, it is also possible to first form chips or pelletsof the resin composition in a melt extruder adapted to rereduce the heathistory of the resin composition, and then to convert the resultingchips or pellets into the desired molded article. The operatingconditions for the mold usually include temperatures of 80° to 300° C.and periods of 0.1 to 10 hours and optionally pressures of 5 to 500kg/cm².

By utilizing the various excellent properties mentioned above, moldedarticles prepared from the resin compositions of this invention can besuitably used as electric and electronic component parts such as printedcircuit boards, switch boxes and circuit board for computers; castingmolds for thermoplastic resins; electrolytic cells; gears, bearings andtypes; heat insulating boards or structural materials for internalcombustion engines; interior and structural materials such as automotiveor aircraft dashboards; and sealing materials such as packing gasketsfor the opening and closing portions of refrigerators and tanks forchemicals.

Embodiment 2

The resin composition of this invention in accordance with embodiment 2contains a rubbery elastic material in addition to the granular orpowdery resin.

The rubbery elastic material is a material which exhibits so-calledrubbery elasticity either as such or in the cured state. Such a rubberyelastic material is well known in the art, and includes, for example,natural rubber and synthetic rubbers such as polybutadiene,polyisoprene, copoly(butadiene-styrene),copoly(butadiene-acrylonitrile), copoly(ethylene-propylene),polyisobutylene, copoly(isobutylene-isoprene), polychloroprene,polyacrylate rubber, polysulfide, silicone rubbers, chlorinatedpolyethylene, fluorine rubber, chlorosulfonated polyethylene, andpolyurethan.

Conveniently, these rubbery elastic materials are used in the uncuredstate.

Among the above examples of the rubbery elastic mateials,copoly(butadiene-acrylonitrile), polyacrylate rubber, fluorine rubber,copoly(butadiene-styrene), polychloroprene, chlorinated polyethylene,chlorosulfonated polyethylene, copoly(ethylene-propylene), and siliconerubbers are preferred in this invention.

The resin composition of this invention containing the rubbery elasticmaterial gives a cured product which has better heat resistance,abrasion resistance, adhesion, compression strength, hardness or tearstrength than a resin composition containing a conventionalphenol-aldehyde resin.

In the resin composition of this invention, the granular or powderyresin has a better action of curing or thickening rubber than aconventional phenol-aldehyde resin.

The mixing ratio of the elastic material and the granular or powderyresin in the resin composition of this invention differs depending uponthe type of the elastic material or the properties of the resin, forexample, its methylol group content, or the end use of the composition.Generally, the granular or powdery resin is used in an amount of notmore than 2 parts by weight, preferably 0.03 to 2 parts by weight,especially preferably 0.05 to 1.5 part by weight, above all 0.1 to 1part by weight, per part by weight of the rubbery elastic material.

In addition to the rubbery elastic material and the granular or powderyresin, the resin composition of this invention may contain variousconventional additives for rubber compounds, such as vulcanizers,vulcanization aids, vulcanization accelerators, protective agents forrubber, processing agents for rubber, reinforcing agents, extenders andcoloring agents.

Examples of the vulcanizers include sulfur- or oxime-type vulcanizerssuch as sulfur, selenium, tellurium, sulfur chloride,p,p'-dibenzoylquinone dioxime and p-quinonedioxime; and organicperoxides such as 1,1-bis(t-butyl)peroxy-3,3,5-trimethylcyclohexane,benzoyl peroxide, t-butylperoxyisopropyl carbonate, dicumyl peroxide,t-butylcumyl peroxide, methyl ethyl ketone peroxide, and cumylhydroperoxide.

Examples of the vulcanization aids includes zinc oxide, lead white,calcium hydroxide, litharge, stearic acid, oleic acid, lauric acid,linseed oil, cottonseed fatty acid, zinc stearate, lead oleate,dibenzylamine, diphenylguanidine phthalate, dibutyl ammonium oleate,diethanolamine and monoethanolamine.

Examples of the vulcanization accelerators include guanidines such asdiphenylguanidine, triphenylguanidine and diphenylguanidine phthalate;aldehyde and ammonia type accelerators such as hexamethylenetetramine,acetaldehyde and ammonia; amines or nitroso compounds such as anacetaldehyde/aniline mixture, an anhydrous formaldehyde/p-toluidinemixture, a butyraldehyde/ethylene polyamine mixture, or a condensationproduct of acrolein and an aromatic amine; thiazoles such as2-mercaptobenzothiazole, dibenzothiazyl disulfide andcyclohexylbenzothiazyl sulfenamide; thioureas such as thiocarbanilideand trialkylthioureas; thio-acid salts and dithio-acid salts such aszinc butylxanthate, zinc dimethyldithiocarbamate, zincisopropylxanthate, sodium diethyldithiocarbamate, palladiumdimethyldithiocarbamate, copper dimethyldithiocarbamate and leadpentamethylenedithiocarbamate; thiurams such as tetramethylthiurammonosulfide, tetramethylthiuram disulfide and dipentamethylenethiuramtetrasulfide; and mixtures of two or more of the above-exemplifiedvulcanization accelerators.

The vulcanizers, vulcanization aids or vulcanization accelerators mayeach be included in an amount of preferably 0.001 to 0.1 part by weightper part by weight of the rubbery elastic material in the resincomposition of this invention.

Examples of the protective agents for rubber include antioxidants suchas N-phenyl-1-naphthylamine, p-(p-tolyl-sulfonylamide)diphenylamine,phenylisopropyl p-phenylenediamine, and p-phenylphenol; antiozonantssuch as p-phenylene diamine,6-amino-2,2,4-trimethyl-2,2-dihydroqyinoline and nickeldibutyldithiocarbamate; crack inhibitors such asN-phenyl-2-naphthylamine and N,N'-diphenylethylenediamine; andinhibitors against the deleterious effects of copper, such asdi-β-naphthyl p-phenylenediamine and Calgon.

Examples of the processing agents for rubber include plasticizers orsoftening agents such as various esters, ketones, aromatic hydrocarbons,alcohols, mineral and vegetable oils, and coal tar products; binderssuch as phenolic resins, coumarone-indene resin and terpene styrene-typeresins; dispersing agents such as fatty acids, fatty acid soaps andamines; and combustion inhibitors such as trixylenyl phosphate andtricresyl phosphate.

Examples of the reinforcing agents include inorganic reinforcing agentssuch as carbon black, zinc oxide, clay, magnesium carbonate, variousgrades of silica, silicates, and calcium carbonate; and organicreinforcing agents such as asphaltic materials, phenolic resins, terpeneresins, coumarone-indene resin, various natural fibers, and varioussynthetic and semi-synthetic fibers.

Examples of the extenders are clay, talc, chalk, barite, lithopone,magnesium carbonate, zinc oxide and caldium carbonate.

Examples of the coloring agents include inorganic pigments such asvarious carbon blacks, titanium white, zinc oxide, red iron oxide, ironblue, cobalt blue, yellow ocher, chrome green and chrome orange; andorganic pigments such as phthalocyanine blue, Para Red, Hansa Yellow andorange lake.

The aforesaid rubber protecting agents, rubber processing agents,reinforcing agents, extenders or coloring agents are may be included inthe resin composition of this invention in an amount of up to 1 part byweight per part by weight of the rubbery elastic material.

The resin composition of this invention according to embodiment 2 may beprepared by melt-mixing the rubbery elastic material, the granular orpowdery resin and the various additives usually at a temperature of 70°to 150° C. using an open roll for example; or by mixing these materialtogether with a solvent suitable for the rubbery elastic material, suchas toluene, xylene, perchloroethylene, trichloroethylene, ketone, ether,alcohol, ethyl acetate, gasoline or light oil, and thereafter subjectingthe mixture to a solvent-removing treatment. During the melt mixing orthe solvent mixing and the solvent removing treatment, the curing of theresin composition of this invention proceeds, but such a resincomposition which has undergone curing reaction to some extent is alsoincluded within the resin composition of this invention.

Articles obtained by heat-treating the resin composition of thisinvention at a temperature of, for example, 100° to 200° C., such as oilseals, gaskets, packings, oil-resistant hoses, conveyor belts, rubberrolls, window frame rubbers, tires, diaphragms, electric componentparts, shoe soles and shoe heels, have excellent mechanical propertiessuch as excellent strength, high hardness, low compression set, andexcellent dimensional stability, or excellent electrical insulation orheat resistance, which are desirable for the respective articles.

Embodiment 3

According to this embodiment, the resin composition of this invention isa curable resin composition comprising the granular or powderyphenol-aldehyde resin, and either another curable resin, or a fillermaterial or both.

Heat-curable or thermosetting resin is preferably used as the curableresin. Examples include resol resins, novolak resins, epoxy resins,furane resins, melamine resins, urea resins, and unsaturated polyesterresins. The resol, novolak, epoxy and furane resins are especiallypreferred. These curable resins may be used singly or as a mixture oftwo or more.

The filler material is included into the curable resin composition ofthis invention for various purposes. For example, for the purpose ofstrengthening a cured molded article prepared from it, or of impartingdimensional stability, heat resistance, fire retardancy, moldability orpocessability to the resin composition, filler materials which areusually used for such purposes can be used in this invention.

The filler material may be an inorganic or organic material, and may begranular or powdery or fibrous. Illustrative of such a filler materialare fibrous inorganic materials such as glass fibers, carbon fibers androck wool; carbon powder, silica, alumina, and silica-alumina; granularor powdery inorganic materials such as diatomaceous earth, calciumcarbonate, calcium silicate, magnesium oxide, clay, antimony oxide,hollow microspheres, or powders of metals such as iron, nickel orcopper; and organic materials such as wood flour, linter, pulp orpolyamide fibers.

The heat-curable resin composition of this invention comprises thegranular or powdery resin and one or both of the curable resin and thefiller.

Strictly, the suitable mixing ratio of these components in theheat-curable resin composition of this invention varies depending uponthe properties of the granular or powdery phenol-aldehyde resin used,for example whether it is heat-fusible or not, or upon the types of thecurable resin and the filler materials. The resin composition of thisinvention may contain the curable resin in an amount of 10 to 90% byweight, preferably 16 to 80% by weight, more preferably 24 to 70% byweight, based on the total amount of the curable resin and the granularor powdery phenol-aldehyde resin.

The heat-curable resin composition of this invention may generallycontain the filler material in an amount of 5 to 89% by weight,preferably 10 to 77% by weight, more preferably 15 to 63% by weight,based on the total amount of the filler and the granular or powderyphenol-aldehyde resin in the composition.

The heat-curable resin composition of this invention encompasses thefollowing three embodiments.

According to a first embodiment, the resin composition comprises all ofthe three components, i.e. the granular or powdery phenol-aldehyderesin, the curable resin and the filler. The granular or powderyphenol-formaldehyde resin contains reactive methylol groups.Accordingly, a cured product obtained from the resin composition isbelieved to have such a structure that the filler material is dispersedin a matrix composed of a cured intimate mixture of the granular orpowdery phenol-aldehyde resin and the curable resin. The powdery orgranular phenol-aldehyde resin may be the heat-fusible species (i), thesubstantially heat-infusible species (ii) or a mixture of (i) and (ii).It is believed that where the heat-fusible species (i) is a majorportion of the resin components, the particles of the granular orpowdery resin are bonded to each other during heat molding as a resultof melting and therefore are greatly disintegrated or form a continuousphase in the resulting cured article. On the other hand, it is believedthat where the granular or powdery resin constitutes a minor portion ofthe resin component, the individual particles of the granular or powderyresin, whether it is the species (i) or (ii), are cured and dispersedwithin the cured matrix in the cured article like independent islands,and act like a filler.

The heat curable resin composition in accordance with the firstembodiment comprises 10 to 85 parts by weight, preferably 20 to 75 partsby weight, above all 30 to 65 parts by weight, of the granular orpowdery resin, 10 to 85 parts by weight, preferably 15 to 70 parts byweight, above all 20 to 55 parts by weight, of the curable resin, and 5to 80 parts by weight, preferably 10 to 65 parts by weight, above all 15to 50 parts by weight, of the filler material, the total amount of thethree components being 100 parts by weight.

It is especially preferred in the first embodiment that the curableresin be a resol resin, a novolak resin or an epoxy resin, and the fiberbe glass fibers.

According to a second embodiment, the resin composition of thisinvention comprises the granular or powdery phenol-aldehyde resin andthe filler and is substantially free from the curable resin.

The granular or powdery resin may be the heat-fusible species (i) or amixture of the heat-fusible species (i) and the substantiallyheat-infusible species (ii). In the case of the mixture of the species(i) and (ii), it is preferred that the species (i) be used in a largeramount than the species (ii) and its amount be at least 25% by weightbased on the total weight of the granular or powdery resin and thefiller material.

The heat-fusible species (i) of the granular or powdery resin used inthis invention, even when molded singly under heat, can give a curedarticle having the inherent excellent properties such as excellentelectrical properties of the cured phenolic resin. As statedhereinabove, it is extremely difficult to prepare a cured molded articlefrom the resol resin alone, and the novolak resin can by itself give acured molded article but its quality is inferior. In view of this fact,the present invention has brought about an innovative advance in the artin that the granular or powdery resin used in this invention can byitself give a feasible cured article easily within very short periods oftime.

A cured article obtained from the resin composition in accordance withthe second embodiment is of very uniform quality because its matrix isderived only from the granular or powdery resin (not containing thecurable resin), and it has particularly excellent heat resistance andelectrical insulation.

The heat-curable resin composition of this invention comprises 20 to 95parts by weight, preferably 30 to 90 parts by weight, more preferably 40to 85 parts by weight, of the granular or powdery resin, and 5 to 80parts by weight, preferably 10 to 70 parts by weight, more preferably 15to 60 parts by weight, of the filler material, the total weight of thetwo components being 100 parts by weight.

Preferably, the filler material used in the second embodiment is glassfibers, hollow microspheres, pulp, carbon powder, calcium carbonate orpolyamide fibers.

According to a third embodiment, the resin composition of this inventioncomprises the granular or powdery phenol-aldehyde resin and the curableresin and is substantially free from the filler material. The granularor powdery phenol-aldehyde resin used in this embodiment may be theheat-fusible species (i), the substantially heat-infusible species (ii),or a mixture of the species (i) and (ii). The substantiallyheat-infusible species (ii) or a mixture of it with the species (i) ispreferred. The substantially heat-infusible species (ii) is used in amamount of 5 to 90% by weight, preferably 10 to 80% by weight, above all15 to 70% by weight, based on the total weight of the resin components.

The heat-curable resin composition according to the third embodimentcomprises 10 to 90 parts by weight, preferably 20 to 80 parts by weight,more preferably 30 to 70 parts by weight, of the granular or powderyresin, and 10 to 90 parts by weight, preferably 20 to 80 parts byweight, more preferably 30 to 70 parts by weight, of the curable resin.

In the third embodiment, the curable resin is preferably a resol resinor a novolak resin.

Unlike the novolak resin, the granular or powdery phenol-aldehyde resinused in the heat-curable resin composition of this invention has verycharacteristic reactivity such that it can be cured without using acrosslinking agent such as hexamine (in this sense, this resin may besaid to be self-curable). This characteristic reactivity is exhibited inthe production of a cured article from the heat-curable resincomposition of this invention. For example, the heat-fusible species ofthe granular or powdery resin reacts with the curable resin such as anovolak resin or a filler material such as polyamide fibers used at thetime of the curing reaction and can by itself cure without acrosslinking agent. Hence, a homogeneous cured article cured to a veryhard structure can be obtained.

When heated, the substantially heat-infusible species of the granular orpowdery resin itself further undergoes curing while substantiallymaintaining its particulate form, and at the same time reacts with theother curable resin at its interface. It, therefore, exhibits anexcellent action as a filler in the cured product, and a very hard curedarticle of uniform quality is obtained.

The heat-curable resin composition can be produced by mixing thegranular or powdery resin and the curable resin and/or the fillermaterial by using a V-blender, for example, if they are solidsubstances. When a solvent solution of a curable resin such as a resolresin or a furan resin is used, the resin composition may be prepared byfirst mixing these materials in a kneader, a mixer, a roll, etc., andthen removing the solvent.

The curable heat-curable resin composition of this invention may beconverted to a cured article by heat-treating it at a temperature of,for example, 80° to 250° C., for 0.1 to 10 hours, and as required underan elevated pressure of 1 to 500 kg/cm². Usually, the resin compositionis first molded and then heat-treated to obtain a cured product.

Cured articles obtained from the heat-curable resin compositions of thisinvention have better compression strength, chemical resistance,electrical properties such as electrical insulation, heat resistance orheat insulation than, for example, cured articles prepared from resincompositions containing conventional phenolic resins.

As required, the resin composition of this invention may contain knownadditives such as ultraviolet absorbers, heat stabilizers, coloringagents, plasticizers, curing agents, accelerators, lubricants andmodifiers.

The following examples illustrate the present invention morespecifically.

The various properties given in the specification including thefollowing examples are measured or defined as follows:

The various abbreviations used in the examples are as follows:

TT: tetramethylthiuram disulfide

DM: dibenzothiazyl sulfide

M: 2-mercaptobenzothiazole

22: mixture of M+TT

ALTAX: benzothiazyl disulfide

Litharge: PbO (acid acceptor)

Light process oil: a kind of oil

DDM: dodecylmercaptan

GMF: accelerator containing p-dinitrosobenzene

TAIC: allyl isocyanurate

DOP: dioctyl phthalate

TET: tetraethyltetramine

1. Content of particles having a specified particle diameter:

A portion weighing about 0.1 g was sampled from five different sites ofone sample.

A part of each of the 0.1 g portions so sampled was placed on a slideglass for microscopic examination. The sample on the slide glass wasspread to minimize accumulation of particles for easy observation.

The microscopic observation was made with regard to that part of thesample in which about 10 to about 50 primary particles and/or thesecondary agglomerated particles thereof were present in the visualfiled of an optical microscope usually having a magnification of 100 to1,000. The sizes of all particles existing in the visual field of theoptical microscope were read by a measure set in the visual field of theoptical microscope and recorded.

The content (%) of particles having a size of, for example, 0.1 to 150μcan be calculated in accordance with the following equation.

    Content (%)=(N.sub.1 /N.sub.o)×100

N_(o) : the total number of particles whose sizes were read in thevisual field under the microscope, and

N₁ : the number of those particles in N_(o) which had a size of 0.1 to150μ.

For each sample, the average of values obtained from the five sampledportions was calculated.

2. Proportion of particles which passed through a Tyler mesh sieve:

About 10 g of a dried sample, if desired after lightly crumpled by hand,was accurately weighed. Over the course of 5 minutes, the sample was putlittle by little in a Tyler mesh sieve vibrator (the opening size of thesieve 200 mm in diameter; vibrating speed 200 rpm). After the end ofaddition, the sieve was vibrated further for 10 minuts. The proportionof the particles which passed through a 100 Tyler mesh sieve, forexample, was calculated from the following equation.

    (% by weight)=[(ω.sub.o -ω.sub.1)/ω.sub.o ]×100

ω_(o) : the amount of the sample put in the sieve (g),

ω₁ : the amount of the sample which remained on the 100 Tyler mesh sieve(g).

3. Free phenol content:

About 10 g of the sample which passed through the 100 Tyler mesh sievewas precisely weighed, and heat-treated under reflux for 30 minutes in190 g of 100% methanol. The hat-treated product was filtered through aNo. 3 glass filter. The filtrate was subjected to high-performanceliquid chromatography to determine the phenol content of the filtrate.The free phenol content of the sample was determined from a calibrationcurve separately prepared.

The operating conditions of high-performance liquid chromatography wereas follows:

Device: Model 6000 A made by Waters Co., U.S.A.

Column carrier: μ-Bondapak C₁₈

Column: 1/4 inch in diameter and 1 foot in length

Column temperature: room temperature

Eluent: methanol/water (3/7 by volume)

Flow rate: 0.5 ml/min.

Detector: UV (254 nm), range 0.01 (1 mV)

The phenol content of the filtrate was determined from a separatelyprepared calibration curve (showing the relation between the phenolcontent and the height of a peak based on phenol).

4. Infrared absorption spectrum and absorption intensities (seeaccompanying FIGS. 1 and 2):

The infrared absorption spectrum of a sample prepared by a usual KBrtablet method was measured by means of an infrared spectrophotometer(Model 225 made by Hitachi Limited).

The absorption intensity at a specified wavelength was determined in thefollowing way.

A base line is drawn tangent to a peak whose absorption intensity is tobe determined in the measured infrared absorption spectral chart. Letthe transmittance of the vertex of the peak be t_(p) and thetransmittance of the base line at the specified wavelength be t_(b),then the absorption intensity D at the specified wavelength is given bythe following equation.

    D=log (t.sub.b /t.sub.p)

For example, the ratio of the absorption intensity of a peak at 890 cm⁻¹to that of a peak at 1600 cm⁻¹ is given by the ratio of the respectiveabsorption intensities determined by the above equation (i.e., D₈₉₀/D₁₆₀₀).

5. Heat fusibility at 100° C.:

About 5 g of a sample which passed through a 100 Tyler mesh sieve wasinterposed between two 0.2 mm-thick stainless steel sheets, and theassembly was pressed under an initial pressure of 50 kg for 5 minutes bymeans of a hot press kept at 100° C. (a single acting compressionmolding machine manufactured by Shinto Kinzoku Kogyosho Co., Ltd.). Thepress was released, and the hot-pressed sample was taken out frombetween the two stainless steel sheets, and observed. When the sample sotaken out was in the form of a flat plate as a result of melting ormelt-adhesion, it was judged that the sample had fusibility. When noappreciable difference was noted after the hot pressing, the sample wasdetermined to have infusibility.

6. Methanol solubility:

About 10 g of a sample was precisely weighed (the precisely measuredweight is given by W_(o)), and heat-treated under reflux for 30 minutesin about 500 ml of 100% methanol. The mixture was filtered on a No. 3glass filter. The sample remaining on the filter was washed with about100 ml of methanol. Then, the sample remaining on the filter was driedat 70° C. for 2 hours. The weight of the dried sample was preciselyweighed (the precisely measured weight is given by W₁). The solubilityof the sample in methanol was calculated from the following equation.

    Solubility in methanol (wt%)=[(W.sub.o -W.sub.1)/W.sub.o ]×100

7. Bulk density:

A sample was poured into a 100 ml measuring cylinder (whose brimcorresponded to a 150 ml indicator mark) from a height 2 cm above thebrim of the measuring cylinder. The bulk density of the sample isdefined by the following equation.

    Bulk density (g/ml)=[W (g)/100 (ml)]

W: the weight in grams of the sample per 100 ml.

8. Weight increase by acetylation

About 10 g of a dry sample was precisely weighed, and added to about 300g of an acetylation bath consisting of 78% by weight of aceticanhydride, 20% by weight of acetic acid and 2% by weight oforthophosphoric acid. Then, the temperature was gradually raised fromroom temperature to 115° C. over the course of 45 minutes. The samplewas further maintained at 115° C. for 15 minutes. Then, the bath wasallowed to cool, and filtered on a No. 3 glass filter while being suckedby an aspirator carefully. The filtrate was fully washed with hot wateron the glass filter, and finally washed with a small amount of coldmethanol. Then, the residue on the glass filter was dried together withthe glass filter in a dissicator at 70° C. for 2 hours, and allowed tostand for a day and night in a dessicator containing silica gel as adrying agent. The dry weight of the residue on the filter was preciselyweighed.

The weight increase by acetylation, I, is given by the followingequation.

    I=[(W.sub.1 -W.sub.o)/W.sub.o ]×100

W_(o) : the precisely measured weight (g) of the dry sample beforeacetylation,

W₁ : the precisely measure weight (g) of the dry sample afteracetylation.

9. Hydroxyl value:

Measured in accordance with the method of measuring the hydroxyl value(General Testing Method 377, Commentary on the Standards of CosmeticMaterials, first edition, published by Yakuji Nipposha, 1975).

10. Compression strength:

Measured in accordance with JIS K-6911-1979.

11. Heat distortion temperature:

Measured in accordance with JIS K-6717.

12. Volume inherent restistivity (ohms-cm):

Measured according to the method described in JIS K-6911-1979.

13. Hardness and tensile strength and elongation:

Measured by the methods described in JIS K-6301-1975.

14. Compression set:

Measured in accordance with the method described in JIS K-6301-1975under the conditions: compression 25%, 70° C.×22 hours.

15. Flexural strength (kg/cm²) and compression strength (kg/cm²):

Measured in accordance with JIS K-6911-1979.

16. Heat resistant temperature:

A sample was heat-treated for 24 hours at various temperatures in adryer. The highest temperature during these heat-treatment operations atwhich no crack or gas blister was observed in the samples is defined asthe heat resistant temperature.

17. Heat conductivity (cal/cm sec °C.):

Measured in accordance with JIS A-1412-1968.

REFERENTIAL EXAMPLE 1

(1) In each run, a 2-liter separable flask was charged with 1,500 g of amixed aqueous solution at 28° C. of hydrochloric acid and formaldehydehaving each of the compositions shown in Table 1, and 62.5 g of anaqueous solution at 25° C. containing 80% by weight of phenol and 5% byweight of formaldehyde prepared from 98% by weight of phenol (theremaining 2% by weight being water), 37% formalin and water was added.The mixture was stirred for 20 seconds, and then left to stand for 60minutes. During the 60-minute standing, the contents of the flaskremained clear (Runs Nos. 1 and 20), or turned from a clear solution toa whitely turbid suspension (Runs Nos. 3, 9 and 18), or turned from aclear solution to a whitely turbid suspension which then turned palepink (Runs Nos. 2, 4 to 8, 10 to 17, and 19). Microscopic observationshowed that the pink-colored suspensions already contained sphericalparticles, agglomerated spherical particles, and a small amount of apowder. With occasional stirring, the contents of the separable flaskwere heated to 80° C. over the course of 60 minutes, and then maintainedat 80° to 82° C. for 15 minutes to obtain a reaction product. Thereaction product was washed with warm water at 40° to 45° C., treated ina mixed aqueous solution containing 0.5% by weight of ammonia and 50% byweight of methanol at 60° C. for 30 minutes, again washed with warmwater at 40° to 45° C., and then dried at 80° C. for 2 hours. Theproperties of the reaction products obtained by using the aqueoussolutions of hydrochloric acid and formaldehyde in various proportionsare shown in Table 2.

(2) For comparison, the following experiment was carried out. A 1-literseparable flask was charged with 282 g of distilled phenol, 369 g of 37%by weight formalin and 150 g of 26% by weight aqueous ammonia and withstirring, the mixture was heated from room temperature to 70° C. over 60minutes. Furthermore, the mixture was stirred at 70° to 72° C. for 90minutes, and then allowed to cool. While 300 g of methanol was addedlittle by little, the product was dehydrated by azeotropic distillationunder a reduced pressure of 40 mmHg. As a solvent, 700 g of methanol wasadded, and the product was withdrawn as a yellowish brown clear solutionof a resol resin.

When the solvent was removed from a part of the resulting resol resinunder reduced pressure, vigorous foaming occurred and the resin wasgelled. The gel was heat-cured under a nitrogen gas atmosphere at 160°C. for 60 minutes, and the resulting cured foam was pulverized to obtaina small amount of a powder which passed through a 100 Tyler mesh sieve.The heat-cured resol was very hard and extremely difficult to pulverizeinto a powder having a size of 100-mesh under even when various types ofpulverizers or ball mills or a vibratory mill for fluorescent X-rayswere used. The resulting heat-cured resol resin powder was treated witha mixed aqueous solution containing 0.5% by weight of ammonia and 50% byweight of methanol, washed with warm water, dehydrated and then driedunder the same conditions as described in section (1) above. Theproperties of the resulting product are shown in Table 2 as Run No. 21.

A 1-liter separable flask was charged with 390 g of phenol, 370 g of 37%by weight formalin, 1.5 g of oxalic acid and 390 g of water, and withstirring, the mixture was heated to 90° C. over 60 minutes and heatedwith stirring at 90° to 92° C. for 60 minutes. Then, 1.0 g of 35% byweight hydrochloric acid was added, and the mixture was further heatedwith stirring at 90° to 92° C. for 60 minutes. The product was cooled byadding 500 g of water, and then the water was removed by a siphon. Theresidue was heated under a reduced pressure of 30 mmHg, and heated underreduced pressure at 100° C. for 3 hours and then at 180° C. for 3 hours.On cooling, a novolak resin was obtained as a yellowish brown solidhaving a softening temperature of 78° to 80° C. and a free phenolcontent, measured by liquid chromatography, of 0.76% by weight. It has amethanol solubility of 100% by weight.

The resulting novolak resin was pulverized and mixed with 15% by weightof hexamethylenetetramine. The mixture was heat-cured in a nitrogen gasat 160° C. for 120 minutes, pulverized in a ball mill, and then passedthrough a 100 Tyler mesh sieve. The resulting powder was treated with amixed aqueous solution containing 0.5% by weight of ammonia and 50% byweight of methanol, washed with water, dehydrated and then dried underthe same conditions as described above. The properties of the resultingproduct are shown in Table 2 as Run No. 22.

The novolak resin was melt-spun at 136° to 138° C. through a spinnerethaving 120 orifices with a diameter of 0.25 mm. The as-spun filamentshaving an average size of 2.1 denier were dipped in a mixed aqueoussolution containing 1.8% by weight of hydrochloric acid and 18% byweight of formaldehyde at 20° to 21° C. for 60 minutes, heated to 97° C.over 5 hours, and then maintained at 97° to 98° C. for 10 hours. Theresulting cured novolak fibers were treated with a mixed aqueoussolution containing 0.5% by weight of ammonia and 50% by weight ofmethanol, washed with water, dehydrated and then dried under the sameconditions as described above. The product was pulverized in a ballmill, and passed through a 100 Tyler mesh sieve. The properties of theresulting product are shown in Table 2 as Run No. 23.

(3) Table 1 shows the concentrations of hydrochloric acid andformaldehyde used and the total concentration of hydrochloric acid andformaldehyde, and the mole ratio of formaldehyde to phenol. Table 2shows the contents of particles having a size of 1 to 50 microns, 1 to100 microns, and 1 to 150 microns, respectively, the proportion ofparticles which passed through a 100 Tyler mesh sieve, the D₉₉₀₋₁₀₁₅/D₁₆₀₀ and D₈₉₀ /D₁₆₀₀ ratios of the resulting products, and the weightincrease by acetylation of the products.

                  TABLE 1    ______________________________________    Run   Concentration (wt. %)                              Mole ratio of form-    No.   HCl    Formaldehyde Total aldehyde to phenol    ______________________________________    1      3     1             4    1.1    2      3     25           28    23.8    3      5     5            10    4.9    4      5     10           15    9.6    5      5     22           27    20.9    6      7     30           37    28.5    7     10     6            16    5.8    8     10     20           30    19.1    9     12     3            15    2.8    10    15     5            20    4.9    11    15     25           40    23.8    12    18     10           28    9.6    13    20     7            27    16.8    14    22     4            26    4.0    15    22     17           39    16.2    16    25     6            31    5.8    17    25     25           50    23.8    18    28     3            31    2.8    19    28     7            35    6.8    20    33     1            34    1.1    21    Heat cured resol resin    22    Hexamine heat-cured novolak resin    23    Cured novolak fibers    ______________________________________

                                      TABLE 2    __________________________________________________________________________                   Proportion of       Content (%) of particles                   particles hav-       having the following                   ing a size of         Weight increase    Run       sizes       100 mesh under                           IR intensity ratio                                         by acetylation    No.       1-50μ           1-100μ               1-150 μ                   (wt. %) D.sub.990-1015 /D.sub.1600                                   D.sub.890 /D.sub.1600                                         (wt. (%)    __________________________________________________________________________     1  1   1   1   1      0.35    0.10   8.6       (76)           (100)               (100)                   (83)     2  3   3   3   4      0.45    0.11  19.5       (73)           (100)               (100)                   (79)     3 13  13   13  8      0.42    0.11  21.7       (87)           (100)               (100)                   (75)     4 50  89   96 62      0.86    0.18  25.4     5 53  97  100 63      4.82    0.73  27.8     6 12  12   12 18      6.68    1.02  30.6       (76)           (100)               (100)                   (84)     7 61  98  100 63      0.23    0.10  25.7     8 83  100 100 78      2.36    0.58  33.5     9 61  92  100 61      0.21    0.14  26.3    10 83  100 100 76      0.25    0.11  28.1    11 63  81  100 61      4.83    0.46  30.5    12 99  100 100 98      1.52    0.40  32.8    13 99  100 100 91      0.83    0.25  31.4    14 69  94  100 69      0.26    0.17  24.7    15 54  75   92 71      2.16    0.64  29.9    16 84  98  100 79      0.37    0.12  28.5    17 10  10   10  2      4.26    0.13  41.3       (86)           (94)               (100)                   (73)    18 50  87   96 62      0.27    0.10  23.8    19 59  93  100 69      0.44    0.10  27.6    20  2   2   2   1      0.23    0.10  19.7       (52)           (95)               (100)                   (61)    21 17  --  --  --      0.12    0.09   9.9    22 58  --  --  --      5.47    0.07  18.7    23 39  --  --  --      0.87    0.23  22.6    __________________________________________________________________________

In Runs Nos. 1, 2, 3, 6, 17 abd 20 shown in Table 1, a large amount of asticky resin or a hard and large lumpy or plate-like mass formed at thebottom of the separable flask. In Runs Nos. 1, 2 and 20, only less than49 g of a solid was obtained from 50 g of phenol used.

In Runs Nos. 1, 2, 3, 6, 17 and 20, the contents of particles having asize of 1 to 50 microns, 1 to 100 microns and 1 to 150 microns and theproportion of particles having a size of 100 mesh under shown in Table 2are based on the entire solid including the sticky resin, lumpy mass andplate-like mass. The contents of these particles and the proportion ofparticles having a size of 100 mesh under based only on the granular andpowdery product in these Runs are shown in the parentheses in Table 2.

REFERENTIAL EXAMPLE 2

Each of six 20-liter reaction vessels was charged with 10.2 to 11.7 kgof a mixed aqueous solution containing 20% by weight of hydrochloricacid and 11% by weight of formaldehyde so that the bath ratio was asshown in Table 3. With stirring at 23° C., a mixed aqueous solutioncontaining 90% by weight of phenol and 3.7 % by weight of formaldehydewas added in an amount of 1.8 kg, 1.5 kg, 0.9 l kg, 0.7 kg, 0.4 kg, and0.25 kg, respectively. The bath ratios were 7.3, 8.5, 13.5, 17.0, 28.9,and 45.6, respectively.

In all of these cases, continued stirring after addition of the mixedaqueous phenol solution resulted in the abrupt formation of whitesuspended particles in 40 to 120 seconds. The stirring was stopped assoon as the white suspended particles formed, and the suspension wasleft to stand for 3 hours. The temperature of the inside of the reactionsystem gradually rose, and the contents of the vessel gradually turnedpale pink. In all of these runs, the formation of a slurry-like orresin-like product was observed in 30 minutes after the formation of thewhite suspended particles. The reaction mixture was washed with waterwith stirring. With stirring, the contents of the flask were heated to75° C. over 2 hours, and then heated with stirring at 75° to 76° C. for30 minutes. With the reaction mixture obtained in a system having a bathratio of 7.3, a large amount of resin melt-adhered to the stirring rodand the stirring became very difficult. In all runs, the contents of thereaction vessel turned from pale pink to pink and further to red duringthe temperature elevation.

The contents of the flask were then washed with water, treated in amixed aqueous solution containing 0.1% by weight of ammonia and 55% byweight of methanol at 50° C. for 60 minutes, and washed with warm waterat 80° C. for 60 minutes. The resulting granular or powdery product orlumpy mass was crumpled lightly by hand, and dried at 100° C. for 2hours. After the drying, the product had a water content of less than0.2% by weight. The resulting products are designated as samples of RunsNos. 31, 32, 33, 34, 35 and 36 in the increasing order of the bathratio.

Table 3 summarizes the maximum temperature reached of the reactionsystem from the initiation of the reaction to 3 hours after theformation of the white suspended particles; the yield of the reactionproduct; the presence or absence of spherical primary particles bymicroscopic observation; the proportion and bulk density of particleshaving a size of 100 Tyler mesh under in the reaction product; the heatfusibility at 100° C. of the reaction product; the elemental analysisvalues of the product; and the OH value of the product.

                                      TABLE 3    __________________________________________________________________________          Maximum    Proportion    Presence or          temperature                     of the 100                            Bulk density                                   absence of  Elemental          reached of                 Yield                     mesh under                            of the 100                                   spherical                                         Heat- analysis    Run       Bath          the reaction                 (wt.                     particles                            mesh under                                   primary                                         fusibility                                               (wt. %)   OH    No.       ratio          system (°C.)                 %)  (wt. %)                             particles                                   particles                                         at 100° C.                                               C  H O  N value    __________________________________________________________________________    31  7.3          39.5   110 29     0.25   Little                                         Fused 74.5                                                  5.7                                                    19.0                                                       0.6                                                         330    32  8.5          38.5   113 63     0.23   Much  Infusible                                               74.7                                                  5.6                                                    19.3                                                       0.3                                                         335    33 13.5          37.0   115 78     0.21   Mostly                                          "    75.0                                                  5.7                                                    20.0                                                       0.2                                                         360    34 17.0          36.5   118 91     0.20    "     "    75.1                                                  5.7                                                    19.1                                                       0.1                                                         373    35 28.9          35.5   118 98     0.19    "     "    76.3                                                  5.7                                                    18.7                                                       0.0                                                         385    36 45.6          35.0   117 97     0.19    "     "    75.7                                                  5.7                                                    18.3                                                       0.0                                                         377    21 (Comparison;                 --   --    0.67   None   "    78.7                                                  5.7                                                    14.7                                                       0.7                                                         235       see Table 1)    22 (Comparison;                 --  --     0.50    "    Fused 78.1                                                  6.0                                                    13.7                                                       2.3                                                         --       see Table 1)    23 (Comparison;                 --  --     0.27    "    Infusible                                               74.8                                                  5.6                                                    19.2                                                       0.5                                                         325       see Table 1)    __________________________________________________________________________

The OH value of the product obtained in Run No. 22 could not be measuredbecause it fluctuated greatly.

In Run No. 31, a plate-like product and a lumpy product formed in atotal amount of as large as about 70% based on the entire solid formedat the bottom of the flask, and only about 30% of the entire solidconsisted of a granular or powdery product. But about 95% of thegranular or powdery product passed through a 100 Tyler mesh sieve. Theindication "little" for Run No. 31 is because the proportion of thegranular or powdery product based on the entire solid was as small asabout 30%. Hence, the method of Run No. 31 is not recommendable, but theresulting granular or powdery product is included within the granular orpowdery used in this invention.

In Runs Nos. 31 to 36, almost all of the granular or powdery productconsisted of particles having a size of 1 to 100 microns.

REFERENTIAL EXAMPLE 3

One thousand grams of a mixed aqueous solution at 25° C. containing 18%by weight of hydrochloric acid and 9% by weight of formaldehyde was putinto each of six 1-liter separable flasks. The room temperature was 15°C. With stirring, 40 g of phenol diluted with 5 g of water was added ata time of the solution. In each run, the stirring was stopped in 50seconds after the addition of the diluted solution of phenol. In 62 to65 seconds after the stopping of the stirring, white suspended particlesabruptly formed to give a milk-white product. The milk-white productgradually turned pink. The temperature of the liquid gradually rose from25° C., reached a maximum temperature of 35° to 36° C. in 16 to 17minutes after the addition, and then dropped. The reaction mixture wasallowed to stand at room temperature for 0.5 hour (Run No. 41), 1 hour(Run No. 42 ), 2 hours (Run No. 43), 6 hours (Run No. 44), 24 hours (RunNo. 45), and 72 hours (Run No. 46), respectively, washed with water,treated in 1% by weight aqueous ammonia at 15° to 17° C. for 6 hours,washed with water, dehydrated, and finally dried at 40° C. for 6 hours.

Table 4 summarizes the proportion of particles which passed through a100 Tyler mesh sieve, the D₉₉₀₋₁₀₁₅ /D₁₆₀₀ ratio and D₈₉₀₀ /D₁₆₀₀ratios, the methanol solubility and the free phenol content of theproducts.

The samples obtained in Runs Nos. 41 to 46 all fused in a heatfusibility test conducted at 100° C. for 5 minutes.

FIG. 1 shows an infrared absorption spectral chart of the granular orpowdery resin obtained in Run No. 44. FIG. 1 also illustrates the methodof determining t_(p) to t_(b) required for obtaining the absorptionintensity D. A base line is drawn across a certain peak, and t_(p) andt_(b) can be determined as illustrated at the wavelength of the peak.

                                      TABLE 4    __________________________________________________________________________    Proportion of    particles which    passed through              Methanol                                        Free phenol    a 100 Tyler mesh                  IR intensity ratio                                solubility                                        content    Run No.         sieve (wt. %)                  D.sub.990-1015 /D.sub.1600                          D.sub.890 /D.sub.1600                                (wt. %) (ppm)    __________________________________________________________________________    41   59       0.53    0.10  97      310    42   83       0.87    0.12  80      116    43   94       1.06    0.13  71      85    44   97       1.12    0.13  67      74    45   96       1.12    0.14  64      73    46   97       1.13    0.13  63      70    __________________________________________________________________________

REFERENTIAL EXAMPLE 4

A 1000-liter reaction vessel equipped with a stirring rod was chargedwith 800 kg of a mixed aqueous solution at 18° C. containing 18.5% byweight of hydrochloric acid and 8.5% by weight of formaldehyde, andwhile the mixed aqueous solution was stirred, 36.4 Kg of a 88% by weightaqueous solution of phenol at 20° C. was added. After the addition ofall of the aqueous phenol solution, the mixture was stirred for 60seconds. The stirring was then stopped, and the mixture was left tostand for 2 hours. In the reaction vessel, white suspended particlesformed abruptly in 85 seconds after the addition of all of the aqueousphenol solution. The white suspended particles gradually turned palepink, and the temperature of the suspension gradually rose to 34.5° C.and decreased. Thereafter, while the mixed aqueous solution in which thereaction product formed was stirred, a valve secured to the bottom ofthe reaction vessel was opened, and the contents were withdrawn andseparated into the reaction product and the mixed aqueous solution ofhydrochloric acid and formaldehyde by using a nonwoven fabric (Nomex, atradename for a product of E. I. du Pont de Nemours & Co.). The reactionproduct was washed with water, dehydrated, dipped for a day and night ina 0.5% by weight aqueous solution of ammonia at 18° C., again washedwith water, and dehydrated to give 44.6 kg of the reaction producthaving a water content of 15% by weight.

2.0 Kg of the reaction product so obtained was dried at 40° C. for 3hours to give 1.7 kg of a sample (Run No. 47).

Table 5 shows the contents of 0.1-50 micron particles and 0.1-100 micronparticles of the dried sample obtained, the proportion of particleswhich passed through a 100 mesh Tyler mesh sieve, the D₉₉₀₋₁₀₁₅ /D₁₆₀₀and D₈₉₀ /D₁₆₀₀ ratios, and the methanol solubility of the product.

                                      TABLE 5    __________________________________________________________________________                        Proprotion of    Content of  Content of                        particles which    0.1-50 micron                0.1-100 micron                        passed through    particles   particles                        Tyler mesh                                 IR intensity ratio                                               Methanol solu-    Run No.         (%)    (%)     sieve (wt. %)                                 D.sub.990-1015 /D.sub.1600                                         D.sub.890 /D.sub.1600                                               bility (wt. %)    __________________________________________________________________________    47   96     100     99       1.18    0.13  47    __________________________________________________________________________

EXAMPLE 1

One part by weight of chips of 6-nylon (1013B, a tradename for a productof Ube Industries, Ltd.) was mixed with the granular or powdery resinobtained in Run No. 35 in an amount of 0, 0.015, 0.025, 0.04, 0.07,0.15, 0.4 and 0.8 part by weight, respectively. The mixture was kneadedand extruded by an extruder (Type 3AGM, made by Sumitomo HeavyIndustries, Ltd.), and cooled to form guts. The guts were converted intochips. The eight kinds of chips obtained were each extruded into a moldkept at 80° C. at a cylinder temperature of 250° C. to obtain eightkinds of molded articles each having a width of 5 cm, a length of 20 cmand a thickness of 0.05 cm (Runs Nos. 51 to 58).

Table 6 shows the flow of the mixed resin and the dispersibility of thegranular or powdery resin during extrusion molding, and the heatdistortion temperature, compression strength and volume inherentresistivity before or after boiling in water of each of the moldedarticles.

                                      TABLE 6    __________________________________________________________________________                            Molded article                            Volume inherent    Amount                  resistivity    Heat    (parts by weight)                Processability                            (ohm-cm)                                    Compression                                           distortion    Run       of the product                Flow of     Before                                After                                    strength                                           temperature    No.       of Run No. 35                the resin                     Dispersibility                            boiling                                boiling                                    (kg/mm.sup.2)                                           (°C.)    __________________________________________________________________________    51 0        Excellent                      --    10.sup.12                                10.sup.9                                     8.7    65    52 0.015    Excellent                     Good   10.sup.13                                10.sup.11                                    10.1    73    53 0.025    Excellent                     Excellent                            10.sup.13                                10.sup.11                                    11.5    84    54 0.04     Excellent                     Excellent                            10.sup.13                                10.sup.12                                    13.7    95    55 0.07     Excellent                     Excellent                            10.sup.14                                10.sup.13                                    14.3   101    56 0.15     Excellent                     Excellent                            10.sup.14                                10.sup.13                                    15.1   112    57 0.4      Excellent                     Excellent                            10.sup.14                                10.sup.13                                    15.2   137    58 0.8      Good Excellent                            10.sup.14                                10.sup.13                                    14.5   154    __________________________________________________________________________

EXAMPLE 2

One part by weight of a powder of 12-nylon (3035J, a tradename for aproduct of Ube Industries, Ltd.) was mixed with 0.3 part by weight ofeach of the products of Runs Nos. 12, 21, 22, and 23 and glass staples(10 microns in diameter and 2 mm in length). The resulting mixtures weremolded into five types of molded articles (Runs Nos. 61 to 65) inaccordance with the method described in Example 1.

Table 7 shows the moldability of each of the mixtures and thecompression strength and the volume inherent resistivity before or afterboiling in water of each of the molded articles.

                  TABLE 7    ______________________________________                     Volume inherent                     resistivity                               Com-                     (ohm-cm)  pression    Run  Material              Before                                     After strength    No.  mixed     Moldability boiling                                     boiling                                           (kg/mm.sup.2)    ______________________________________    61   Product of                   Very good   10.sup.14                                     .sup. 10.sup.13                                           14.7         Run No. 12    62   Product of                   Non-uniformity                               10.sup.13                                     .sup. 10.sup.10                                           7.3         Run No. 21                   in dispersion    63   Product of                   Much gas    10.sup.12                                     10.sup.8                                           5.1         Run No. 22                   generated    64   Product of                   Great non-  10.sup.13                                     10.sup.9                                           7.2         Run No. 23                   uniformity                   in dispersion    65   Glass     Great non-  10.sup.13                                     10.sup.8                                           7.6         staples   uniformity                   in dispersion    ______________________________________

EXAMPLE 3

One part by weight of each of a polyester resin (BELLPET EFG-6, atradename for a product of Kanebo Synthetic Fibers Co., Ltd.), apolycarbonate resin (MAKROLON 3100, a tradename for a product of BayerAG), a polyethylene resin (Hizex 2000, a tradename for a product ofMitsui Petrochemical Industries, Ltd.), nylon-66 (Nylon 2020, atradename for a product of Ube Industries, Ltd.) and a vinyl chlorideresin (RYULON 7001, a tradename for a product of Tekkosha Co., Ltd.) wasmixed with 0.45 part by weight of the product of Run No. 44. The mixturewas melted at a temperature of 150° to 300° C., and then cooled and cut.One hundred grams of each of the resulting samples was divided into tenequal portions, and treated for 5 minutes under a pressure of 100 to 500kg/cm² in a mold heated in advance to 100° to 250° C. between hotpresses, to obtain ten molded articles (width 13 mm, thickness 5.2-6.8mm, length 100 mm) from each of the samples (Runs Nos. 71 to 75).

Table 8 shows the heat distortion temperature and combustibility (matchtest by contact with the flame of a match for 10 seconds) of each of themolded products as the average properties of the ten samples in eachRun. For comparison, molded articles were produced similarly from thevarious resins alone, and the results are also shown in Table 8 (RunsNos. 76 to 80).

                  TABLE 8    ______________________________________                          Heat                          deform-                          ation                          tem-                          perature  Combustibility    Run No. Resin used    (°C.)                                    a match test    ______________________________________    Invention    71      Polyester resin                          135       Self-extinguishing    72      Polycarbonate resin                          160       Flame retardant    73      Polyethylene resin                           95       Burning very slow    74      Nylon-66 resin                          145       Self-extinguishing    75      Vinyl chloride                          105       Flame-retardant,            resin                   carbonized    Comparison    76      Polyester resin                           70       Burning slow    77      Polycarbonate resin                          130       Self-extinguishing    78      Polyethylene resin                           55       Burning slow    79      Nylon-66 resin                          70        Burning slow    80      Vinyl chloride                          70        Self-extinguishing            resin    ______________________________________

EXAMPLE 4

One part by weight of a powder of 12-nylon (3035J, a tradename for aproduct of Ube Industries, Ltd.) was mixed with 1, 3 or 10 parts byweight of the product of Run No. 47, and the mixture was treated under apressure of 300 kg/cm² for 20 minutes in a mold heated in advance to150° to 170° C. between hot presses to produce ten molded plates (width13 mm, thickness 0.5-0.6 mm, length 100 mm) in each of Runs Nos. 81 to83 as shown in Table 9. For comparison, ten molded plates were preparedfrom a powder of 12-nylon alone under the same conditions as aboveexcept that a mold heated to 150° C. was used (Run No. 84).

Table 9 shows the heat shrinkage residual ratio of each molded sheetupon standing for 30 minutes in a desiccator at 200° C. in the air, theheat fusibility of each plate when it was maintained in an atmosphere ofnitrogen gas at 500° C. for 10 minutes, and the volume inherentresistivity of each molded plate before and after boiling in water.

                  TABLE 9    ______________________________________                 Heat                Volume in-    Product of   shrinkage           herent resistivity    Run No. 47   residual   Heat     (ohm-cm)           (parts by ratio      fusibi-                                       Before                                             After    Run No.           weight)   (%)        lity   boiling                                             boiling    ______________________________________    Invention    81     1         95.4       Heat-  10.sup.14                                             10.sup.13                                infusible    82     3         98.6       Heat-  10.sup.14                                             10.sup.14                                infusible    83     10        99.5       Heat-  10.sup.14                                             10.sup.14                                infusible    Com-    parison    84     0         No shape   Fused  10.sup.9                                             10.sup.8                     retention    ______________________________________

REFERENTIAL EXAMPLE 5

(1) A 2-liter separable flask was charged with 1.5 kg of a mixed aqueoussolution at 25° C. of hydrochloric acid and formaldehyde in the variousconcentrations shown in Table 10, and while the mixed aqueous solutionwas stirred, 125 g of a mixed aqueous solution at 25° C. containing 20%by weight of phenol, 20% by weight of urea and 14.6% by weight offormaldehyde prepared from 98% phenol (the remaining 2& by weight beingwater), urea, 37% by weight formalin and water was added. The mixturewas then stirred for 15 seconds, and thereafter left to stand for 60minutes. During the 60-minute standing, the contents of the separableflask remained clear (Runs Nos. 101 and 120 in Table 10), or turned froma clear solution to a whitely turbid suspension and remained whitelyturbid (Runs Nos. 103, 109 and 118 in Table 10), or turned from a clearsolution to a whitely turbid suspension and gave a white precipitate(Runs Nos. 102, 104-108, 110-117, and 119). By microscopic observation,this white precipitate was found to contain spherical particles, anagglomerated mass of spherical particles, and a small amount of apowder. Then, with occasional stirring, the contents of the separableflask were heated to 80° C. over 60 minutes and then maintained at 80°to 82° C. for 15 minutes to obtain a reaction product. The reactionproduct was washed with warm water at 40° to 45° C., treated at 60° C.for 30 minutes in a mixed aqueous solution containing 0.5% by weight ofammonia and 50% by weight of methanol, again washed with warm water at40° to 45° C., and then dried at 80° C. for 2 hours. The properties ofthe reaction products are shown in Table 11.

(2) Table 10 summarizes the concentrations of hydrochloric acid andformaldehyde used, the total concentration of hydrochloric acid andformaldehyde, the proportion of the weight of the HCl-formaldehydesolution based on the total weight of the phenol and urea, and the moleratio of formaldehyde to phenol+urea. Table 11 summarizes the contentsof particles having a size of 0.1 to 50 microns and 0.1 to 100 micronsrespectively, the amount of particles which passed through a 150 Tylermesh sieve, and the D₉₆₀₋₁₀₂₀ /D₁₄₅₀₋₁₅₀₀, D₁₂₈₀₋₁₃₆₀ /D₁₄₅₀₋₁₅₀₀ andD₁₅₈₀₋₁₆₅₀ /D₁₄₅₀₋₁₅₀₀ ratios of the resulting products.

                                      TABLE 10    __________________________________________________________________________                    Proportion of the weight of    Concentrations of the                    the HCl--HCHO bath based on the    HCl--formaldehyde                    total amount of phenol and urea                                     Mole ratio of total    (wt. %)         (wt. %)          HCHO to the mixture    Run No.         HCl            HCHO                Total                    HCl     HCHO     of phenol and urea    __________________________________________________________________________    101   3 1    4   90      30      1.6    102   3 28  31   90     840      21.2    103   5 2    7  150      60      2.3    104   5 10  15  150     310      8.1    105   5 22  27  150     660      16.8    106   7 30  37  210     900      22.6    107  10 7   17  300     210      5.9    108  10 18  28  300     540      13.9    109  12 3   15  360      90      3.0    110  15 5   20  450     150      4.5    111  15 22  37  450     660      16.8    112  18 10  28  540     300      8.1    113  20 7   27  600     210      5.9    114  22 4   26  660     120      3.8    115  22 17  39  660     510      13.2    116  25 6   31  750     180      5.2    117  25 25  50  750     750      19.0    118  28 3   31  780     790      2.6    119  28 7   35  780     210      5.9    120  33 1   35  990      30      1.6     21  Heat-cured product of resol     22  Hexamine heat-cured product of novolak     23  Cured novolak fibers    __________________________________________________________________________

                                      TABLE 11    __________________________________________________________________________    Content of   Content of                         Proportion of    particles with                 particles with                         particles which    a size of    a size of                         passed through                                  IR intensity ratio         0.1-50  0.1-100 a 150 Tyler mesh                                  D.sub.1580-1650 /                                        D.sub.1280-1360 /                                              D.sub.960-1020 /    Run No.         microns (%)                 microns (%)                         sieve (wt. %)                                  D.sub.1450-1500                                        D.sub.1450-1500                                              D.sub.1450-1500    __________________________________________________________________________    101  13 (86) 13 (100)                         13 (87)  0.31  0.29  0.10    102  6 (45)  6 (58)  6 (52)   0.46  0.53  0.53    103  32 (91) 32 (98) 32 (93)  0.73  0.46  0.14    104  56      78      65       1.67  0.73  0.45    105  38      47      58       1.41  0.86  0.47    106  7 (18)  7 (39)  7 (66)   1.36  0.75  0.48    107  99      99      93       1.34  0.88  0.31    108  90      99      88       1.26  0.97  0.38    109  78      85      72       1.18  0.65  0.29    110  92      100     87       1.29  0.96  0.23    111  43      87      68       1.16  0.85  0.37    112  100     100     100      1.37  1.10  0.29    113  100     100     100      1.26  1.08  0.26    114  72      77      66       1.38  0.54  0.19    115  50      76      76       1.54  0.97  0.56    116  84      96      81       1.49  0.66  0.31    117  10 (63) 10 (68) 10 (73)  1.01  0.78  0.64    118  38      69      65       1.34  0.47  0.19    119  46      75      69       1.14  0.77  0.32    120  7 (18)  7 (49)  7 (64)   0.75  0.39  0.12     21  17      --      --       0.22  0.10  0.03     22  58      --      --       0.50  0.13  3.73     23  39      --      --       0.15  0.08  0.14    __________________________________________________________________________

In Runs Nos. 101, 102, 106, 117 and 120 in Table 10, a large amount of asticky resin, a hard large lumpy or plate-like mass formed at the bottomof the separable flasks.

In Runs Nos. 101, 102 and 120, only less than 49 g of a solid wasobtained from 25 g of phenol and 25 g of urea used.

The contents of particles having a size of 0.1-50 microns and 0.1-100microns and the proportion of particles which passed the 150 Tyler meshsieve given in Table 11 for Runs Nos. 101, 102, 103, 106, 117 and 120are based on the entire solid including the sticky resin, lumpy mass andplate-like mass. The contents of these and the proportion of theparticles which passed through the 150 Tyler mesh sieve, based on thegranular or powdery product alone in the resulting solid, are given inthe parentheses in Table 11.

FIG. 2 shows an infrared absorption spectral chart of the granular orpowdery product obtained in Run No. 112, and also illustrates how todetermine t_(p) and t_(b), which are required in obtaining theabsorption intensity D, from the infrared absorption spectral chart. Abase line is drawn across a certain peak, and t_(p) and t_(b) can bedetermined at the wavelength of the peak as illustrated.

REFERENTIAL EXAMPLE 6

Ten kilograms of a mixed aqueous solution containing 18% by weight ofhydrochloric acid and 11% by weight of formaldehyde was put in each ofsix 20-liter reaction vessels in a room kept at a temperature of 21° to22° C. While the mixed aqueous solution was stirred at 23° C., a mixedaqueous solution containing 30% by weight of phenol, 20% by weight ofurea and 11% by weight of formaldehyde was added in an amount of 3.34kg, 2.66 kg, 1.60 kg, 1.06 kg, 0.74 kg, and 0.45 kg, respectively. Thebath ratio at this time was 7.0, 8.5, 13.5, 20.0, 28.0, and 45.0,respectively. In all runs, when the stirring was continued after theaddition of the mixed aqueous solution containing phenol, the mixtureabruptly became whitely turbid in 10 to 60 seconds. The stirring wasstopped as soon as the mixture became whitely turbid. The mixture wasthen left to stand for 3 hours. The temperature of the mixture graduallyrose, and in 30 minutes after it became whitely turbid, the formation ofa white slurry-like or resin-like product was observed. With stirring,the reaction mixture was washed with water. With the reaction mixtureobtained at a bath ratio of 7.0, a large amount of a resinous hardenedproduct melt-adhered to the stirring rod, and the stirring became verydifficult.

The contents of the reaction vessel were treated in a 0.3% by weightaqueous solution of ammonia at 30° C. for 2 hours with slow stirring,washed with water, and dehydrated. The resulting granular or powderyproduct or mass was lightly crumpled by hand, and dried at 40° C. for 3hours. After drying, the products had a water content of less than 0.5%by weight. The contents of the vessels are designated as Runs Nos. 131,132, 133, 134, 135 and 136 in the increasing order of the bath ratio.

Table 12 summarizes the maximum temperature reached of the reactionsystem during the time from the initiation of the reaction to 3 hoursafter the reaction system became whitely turbid, the yield of thereaction product, the presence or absence of spherical primary particlesby microscopic observation, the proportion of particles which passedthrough a 150 Tyler mesh sieve, the bulk density of the particles whichpassed through the 150 Tyler mesh sieve, the heat fusibility of thereaction product at 100° C., the methanol solubility of the product, andthe free phenol content of the product.

                                      TABLE 12    __________________________________________________________________________                           Proportion of                                   Bulk density            Maximum        particles which                                   of the   Presence or            temperature    passed through                                   150 Tyler                                            absence of        Free            of the         a 150 Tyler                                   mesh under                                            spherical    Methanol                                                              phenol         Bath            reaction system                    Yield  mesh sieve                                   particles                                            primary                                                  Flexibility                                                         solubility                                                              content    Run no.         ratio            reached (°C.)                    (wt. %)                           (wt. %) (g/cc)   particles                                                  at 100° C.                                                         (wt.                                                              (ppm)    __________________________________________________________________________    131   7.0            39.5    100    11      0.19     Little                                                  Melt-  83.8 150                                                  adhered    132   8.5            39.0    113    56      0.16     Much  Melt   67.7 50                                                  adhered    133  13.5            38.0    124    88      0.14     Mostly                                                  Melt   60.4 35                                                  adhered    134  20.0            36.5    128    100     0.12     "     Melt   53.6 30                                                  adhered    135  28.0            36.0    128    100     0.11     "     Melt   54.4 25                                                  adhered    136  45.0            36.0    129    99      0.11     "     Melt   52.6 25                                                  adhered     21  (Comparison;                    --      --     0.62     None  Infusible                                                         Not                                                              Below         see Table 1)                                    than                                                              5     22  (Comparison;                    --     --      0.46     "     Melt   1.6  Below         see Table 1)                             adhered     5     23  (Comparison;                    --     --      0.24     "     Infusible                                                         Not                                                              Below         see Table 1)                                    than                                                              5    __________________________________________________________________________

In Table 12, the free phenol contents in Runs Nos. 21, 22 and 23 arevalues measured with regard to resol and novolak resins beforeheat-curing and are indicated in the parentheses.

In Run No. 131 shown in Table 12, a sticky resin and a lumpy mass formedin an amount of about 80% based on the entire solid formed at the bottomof the flask, and the proportion of the resulting granular or powderyproduct was only about 20% based on the entire solid. About 85% of suchgranular or powdery product passed through a 100 Tyler mesh sieve. The"little" in the column of the presence or absence of spherical primaryparticles indicated in Table 12 for Run No. 131 was because theproportion of the granular or powdery product based on the entire solidproduct was as small as about 20%. Hence, the method of Run No. 131cannot be recommended as a manufacturing method, but the resultinggranular or powdery product sufficiently has the properties of thegranular or powdery product suitably used in this invention.

Almost 100% of each of the granular or powdery products obtained in RunsNos. 131 to 136 consisted of particles having a particle size of 0.1 to100 microns.

REFERENTIAL EXAMPLE 7

A 2-liter separable flask was charged with 1,250 g of a mixed aqueoussolution at 24° C. containing 20% by weight of hydrochloric acid and 8%by weight of formaldehyde, and while it was stirred, a solution of eachof the phenols shown in Table 13 and each of the nitrogen compoundsshown in Table 13 diluted to a concentration of 20 to 80% by weight with37% by weight formalin was added so that the total amount of the phenoland the nitrogen-containing compound became 50 g. As soon as thesolution containing the phenol and the nitrogen-containing compound wereadded, the mixture became turbid, and in some Runs, instantaneouslyturned white, pink or brown. In 10 seconds after the addition of thesolution, the stirring was stopped. After the stopping of the addition,the mixture was allowed to stand for 60 minutes. Again with stirring, itwas heated to 75° C. over 30 minutes, and maintained at 73° to 76° C.for 60 minutes. The reaction product was washed with water, treated at45° C. for 60 minutes in a mixed aqueous solution containing 0.3% byweight of ammonia and 60% by weight of methanol, washed with water, andfinally dried at 80° C. for 3 hours.

Table 13 summarizes the types and proportions of the phenol and thenitrogen-containing compound used, the concentrations of the phenol andthe nitrogen-containing compound in the formalin-diluted solution, thecolor of the reaction product observed 60 minutes after the addition ofthe resulting diluted solution, the yield of the reaction product basedon the total amount of the phenol and the nitrogen-containing compound,the content of particles having a size of 0.1 to 50 microns in thereaction product, the proportion of particles which passed through a 150Tyler mesh sieve, the D₉₆₀₋₁₀₂₀ /D₁₄₅₀₋₁₅₀₀ ratio, and the heatresistance of the product.

                                      TABLE 13    __________________________________________________________________________                                Concentration    Proportion of the materials of the material                                         Color of the    used (wt.)                  in the diluted                                         reaction product    Run            Nitrogen-containing                                solution (60 minutes    No.       Phenol      compound     (wt. %)  after addition    __________________________________________________________________________    137       Phenol 100  Urea        0                                80       Pink    138       Phenol 97   "           3                                "        "    139       Phenol 94   "           6                                "        "    140       Phenol 75   "          25                                50       Pale pink    141       Phenol 55   "          45                                40       White color    142       Phenol 35   "          64                                30       "    143       Phenol 25   "          75                                20       "    144       Phenol 10   "          90                                20       "    145       Phenol 50   N,N'--dimethylolurea                              50                                "        "    146       Phenol 75   Aniline    25                                80       Reddish Brown    147       Phenol 50   Melamine   50                                80       White    148       Phenol 50   Urea       50                                40       "    149       Phenol 50   Urea       50                                40       Red    150       Phenol/resorcinol                   Urea       33                                40       Red       (= 34/33)    151       Phenol/t-butyphenol                   Urea       40                                40       Brown       (= 40/20)    152       Phenol 50   Urea/melamine (= 25/25)                                50       White     21       Heat-cured resol resin     22       Hexamine heat-cured novolak resin     23       Cured novolak fibers    __________________________________________________________________________                   Proportion            Contents of                   of particles            the particles                   which passed            having a size                   through a                Heat            of 0.1 to 50                   150 Tyler                          IR intensity ratio                                            resistance    Run       Yield            microns                   mesh sieve                          D.sub.1580-1650 /                                D.sub.1280-1350 /                                      D.sub.960-1020 /                                            test    No.       (wt. %)            (%)    (wt. %)                          D.sub.1450-1500                                D.sub.1450-1500                                      D.sub.1450-1500                                            (°C.)    __________________________________________________________________________    137       118  91      98    0.25  0.18  0.44  750    138       108  90      98    0.27  0.18  0.31  420    139       112  97     100    0.57  0.21  0.30  280    140       128  100    100    1.24  0.95  0.19  200    141       132  100    100    1.32  1.10  0.29  "    142       115  100    100    1.37  1.08  0.29  "    143        76  100    100    1.37  0.99  0.30  "    144        31  100    100    1.24  0.96  0.27  "    145       105  94     100    1.19  0.88  0.38  "    146       101  82      88    1.21  1.03  0.20  "    147        86  100     96    1.15  0.75  0.28  "    148       109  100    100    1.31  1.02  0.27  "    149       100  72      83    1.33  0.99  0.26  "    150       132  91      94    1.25  0.99  0.25  "    151        84  96      96    1.16  0.96  0.19  "    152       102  95     100    1.24  1.01  0.30  "     21     17            0.22  0.10  0.03  720     22     58            0.50  0.13  3.73  610     23     39            0.15  0.08  0.14  740    __________________________________________________________________________

REFERENTIAL EXAMPLE 8

Each of six 1-liter separable flasks was charged with 1,000 g of a mixedaqueous solution at 18° C. containing 18% by weight of hydrochloric acidand 9% by weight of formaldehyde. The room temperature was 15° C. Whilethe solution was stirred, 15 g of urea was dissolved in it, and then 25g of a mixed diluted solution containing 80% by weight of phenol and 5%by weight of formaldehyde was added at a time. Ten seconds after theaddition of the diluted solution, the stirring was stopped, and thesolution was left to stand. In all Runs, the solution abruptly becamewhitely turbid in 18 to 19 seconds after the stopping of the stirring,and the formation of a milk-white product was observed. The temperatureof the solution gradually rose from 18° C., and reached a peak at31°-32° C. in 5 to 7 minutes after the addition of the diluted solutionof phenol, and then decreased. The flask was left to stand at roomtemperature for 0.5 hour (Run No. 161), 1 hour (Run No. 162), 3 hours(Run No. 163), 6 hours (Run No. 164), 24 hours (Run No. 165), and 72hours (Run No. 166), respectively, after the addition of the dilutedphenol solution. Then, the contents of the flask were treated in a 0.75%by weight aqueous solution of ammonia at 15° to 17° C. for 3 hours,washed with water, dehydrated, and finally dried at 40° C. for 6 hours.

Table 14 summarizes the proportion of particles which passed through a150 Tyler mesh sieve, the D₉₆₀₋₁₀₂₀ /D₁₄₅₀₋₁₅₀₀ ratio, the methanolsolubility, and the free phenol content of the resulting dried products.The samples obtained in Runs Nos. 161 to 166 all melt-adhered in afusibility test conducted at 100° C. for 5 minutes.

                  TABLE 14    ______________________________________                   Proportion of         Standing  particles which                               Meth-         time at   passed through                               anol  IR intensity                                             Free         room tem- a 150 Tyler solu- ratio   phenol    Run  perature  mesh sieve  bility                                     D.sub.960-1020 /                                             content    No.  (hours)   (wt. %)     (wt. %)                                     D.sub.1450-1500                                             (ppm)    ______________________________________    161  0.5       63          99.5  0.13    280    162  1         87          97.8  0.17    70    163  3         95          85.7  0.24    45    164  6         100         63.4  0.29    30    165  24        100         40.2  0.29    20    166  72        98          35.6  0.31    15    ______________________________________

REFERENTIAL EXAMPLE 9

A 1000-liter reaction vessel equipped with a stirring rod was chargedwith 800 kg of a mixed aqueous solution at 22.5° C. containing 18.5% byweight of hydrochloric acid and 8.5% by weight of formaldehyde, andwhile the mixed aqueous solution was stirred, 40 kg of a mixed aqueoussolution at 20° C. containing 20% by weight of phenol, 10% by weight ofhydroquinone and 20% by weight of urea was added.

After adding all of the phenol solution, the mixture was stirred for 20seconds. The stirring was stopped, and the mixture was left to stand for2 hours. In the reaction vessel, white suspended particles abruptlyformed in 35 seconds after the addition of all of the phenol solution. Awhite granular product gradually formed, and the temperature of thesuspension gradually rose to 35.5° C. and then decreased. The mixedaqueous solution in which the reaction product formed was again stirred,and a valve secured to the bottom of the reaction vessel was opened towithdraw the contents. By using a nonwoven fabric of Nomex (a tradenamefor a product of E. I. du Pont de Nemours & Co.), the contents wereseparated into the reaction product and the mixed aqueous solution ofhydrochloric acid and formaldehyde. The resulting reaction product waswashed with water, dehydrated, dipped for a day and night in a 0.5% byweight aqueous solution of ammonia at 18° C., again washed with water,and dehydrated to give 29.9 kg of the reaction product having a watercontent of 15% by weight.

2.0 kg of the reaction product thus obtained was dried at 40° C. for 3hours to give 1.7 kg of a sample (Run No. 167).

Table 15 gives the contents of particles having a size of 0.1 to 50microns and particles having a size of 0.1 to 100 microns determined bymicroscopic observation of the resulting dried sample, the proportion ofparticles which passed through a 150 Tyler mesh sieve, and the methanolsolubility of the product.

                  TABLE 15    ______________________________________          Content of                    Content of  Proportion          0.1-50    0.1-100     of particles          micron    micron      150 mesh                                        Methanol    Run   particles particles   under   solubility    No.   (%)       (%)         (wt. %) (wt. %)    ______________________________________    167   100       100         99      58    ______________________________________

EXAMPLE 5

One part by weight of chips of 6-nylon (1013B, a tradename for productof Ube Industries, Ltd.) was mixed with the granular or powdery resinobtained in Run No. 135 in an amount of 0, 0.015, 0.025, 0.04, 0.07,0.15, 0.4 and 0.8 part by weight, respectively. The mixture was kneadedand extruded by an extruder (Type 3AGM, made by Sumitomo HeavyIndustries, Ltd.), and cooled to produce guts. The guts were eachconverted to chips. Eight kinds of chips obtained were each molded in amold kept at 80° C. at a cylinder temperature of 250° C. to give eightkinds of molded articles each having a width of 5 cm, a length of 20 cmand a thickness of 0.5 cm (Runs Nos. 151 to 158).

Table 16 summarizes the flow of the mixed resin and the dispersibilityof the granular or powdery resin during extrusion molding, and thecompression strength and the volume inherent resistivity before or afterboiling in water of each of the molded articles.

                                      TABLE 16    __________________________________________________________________________                               Molded article                               Volume inherent    Amount                     resistivity    (parts by weight)                  Processability                               (ohm-cm)                                       Compression         of the product of                  Flow         Before                                   After                                       strength    Run No.         Run No. 135                  of the resin                        Dispersibility                               boiling                                   boiling                                       (kg/mm.sup.2)    __________________________________________________________________________    171  0        Excellent                        --     10.sup.12                                   10.sup.9                                       8.7    172  0.015    Excellent                        Good   10.sup.12                                   10.sup.10                                       9.5    173  0.025    Excellent                        Excellent                               10.sup.12                                   10.sup.11                                       11.3    174  0.04     Excellent                        Excellent                               10.sup.13                                   10.sup.12                                       13.2    175  0.07     Excellent                        Excellent                               10.sup.13                                   10.sup.13                                       15.6    176  0.15     Excellent                        Excellent                               10.sup.14                                   10.sup.14                                       17.8    177  0.4      Excellent                        Excellent                               10.sup.14                                   10.sup.14                                       17.0    178  0.8      Good  Excellent                               10.sup.14                                   10.sup.13                                       15.1    __________________________________________________________________________

EXAMPLE 6

One part by weight of a powder of 12-nylon (3035B, a tradename for aproduct of Ube Industries, Ltd.) was mixed with 0.3 part by weight ofeach of the products obtained in Runs Nos. 112, 140, 147 and 150, theproducts (cured products) obtained in Runs Nos. 21 to 23, and glassstaples (10 microns in diameter, and 2 mm in length). Each of themixtures was molded as in Example 5 to give 8 kinds of molded articles(Runs Nos. 170 to 186).

Table 17 shows the volume inherent resistivity before and after boilingin water and compression strength of the molded products, and themoldability of the mixed resin.

                  TABLE 17    ______________________________________                    Volume inherent                    resistivity                    (ohm-cm)  Compression    Run  Material             Before                                    After strength    No.  mixed      Moldability                              boiling                                    boiling                                          (kg/mm.sup.2)    ______________________________________    179  Product of Very good 10.sup.14                                    10.sup.13                                          13.8         Run No. 112    180  Product of Very good 10.sup.14                                    10.sup.14                                          14.9         Run No. 140    181  Product of Very good 10.sup.14                                    10.sup.13                                          12.6         Run No. 147    182  Product of Very good 10.sup.14                                    10.sup.13                                          13.1         Run No. 150    183  Product of Non uni-  10.sup.13                                    10.sup.10                                          7.3         Run No. 21 formity in                    dispersion    184  Product of Much gas  10.sup.12                                    10.sup.8                                          5.1         Run No. 22 generated    185  Product of Great non-                              10.sup.13                                    10.sup.9                                          7.2         Run No. 23 uniformity                    in dis-                    persion    186  Glass staples                    Great non-                              10.sup.13                                    10.sup.8                                          7.6                    uniformity                    in dis-                    persion    ______________________________________

EXAMPLE 7

One part by weight of each of a polyester resin (BELLPET EFG-6, atradename for a product of Kanebo Synthetic Fibers Co., Ltd.), apolycarbonate resin (MAKROLON 3100, a tradename for a product of BayerAG), a polyethylene resin (Hizex 2000, a tradename for a product ofMitsui Petrochemical Industries, Ltd.), nylon-66 (Nylon 2020, atradename for a product of Ube Industries, Ltd.) and a vinyl chlorideresin (RYULON 7001, a tradename for a product of Tekkosha Co., Ltd.) wasmixed with 0.45 part by weight of the product of Run No. 164. Themixture was melted at a temperature of 150° to 300° C., and then cooledand cut. One hundred grams of each of the resulting samples was dividedinto ten equal portions, and treated for 5 minutes under a pressure of100 to 500 kg/cm² in a mold heated in advance to 100° to 250° C. betweenhot presses to obtain ten molded articles (width 13 mm, thickness5.2-6.8 mm, length 100 mm) from each of the samples (Runs Nos. 187 to191) shown in Table 18.

Table 18 shows the heat distortion temperature and combustibility (matchtest by contact with the flame of a match for 10 seconds) of each of themolded products as the average properties of the ten samples in eachRun. For comparison, molded articles were produced similarly from thevarious resins alone and the results are also shown in Table 18 (RunsNos. 192 to 196).

                  TABLE 18    ______________________________________                          Heat                          deform-                          ation                          temper-                          ature     Combustibility by    Run No. Resin used    (°C.)                                    a match test    ______________________________________    Invention    187     Polyester resin                          140       Self-extinguishing    188     Polycarbonate resin                          175       Flame-retardant,                                    carbonized    189     Polyethylene resin                           90       Burning very slow    190     Nylon-66 resin                          155       Flame-retardant,                                    carbonized    191     Cinyl chloride                          120       Flame-retardant,            resin                   carbonized    Comparison    192     Polyester resin                           70       Burning slow    193     Polycarbonate resin                          130       Self-extinguishing    194     Polyethylene resin                           55       Burning slow    195     Bylon-66 resin                           70       Burning slow    196     Vinyl chloride                           70       Self-extinguishing            resin    ______________________________________

EXAMPLE 8

One part by weight of a powder of 12-nylon (3035J, a tradename for aproduct of Ube Industries, Ltd.) was mixed with 1, 3 or 10 parts byweight of the product of Run No. 167, and the mixture was treated undera pressure of 300 kg/cm² for 20 minutes in a mold heated in advance to150° to 170° C. between hot presses to produce ten molded plates (width13 mm, thickness 0.5-0.6 mm, length 100 mm) in each of Runs Nos. 197 to199 as shown in Table 19. For comparison, ten molded plates wereprepared from a powder of 12-nylon alone under the same conditions asabove except that a mold heated to 120° C. was used (Run No. 200).

Table 19 shows the heat shrinkage residual ratio of each of the moldedplates upon standing for 30 minutes in a desiccator at 200° C. in theart, the heat fusibility of each molded plate when it was maintained ina nitrogen atmosphere at 500° C. for 10 minutes, and the compressionstrength of each molded plate.

                  TABLE 19    ______________________________________                      Heat           Product of shrinkage           Run No. 167                      residual          Compression           (parts by  ratio      Heat   strength    Run No.           weight)    (%)        fusibility                                        (kg/mm.sup.2)    ______________________________________    Invention    197    1          96.8       Heat-  15.2                                 infusible    198    3          99.0       Heat-  16.4                                 infusible    199    10         99.3       Heat-  19.7                                 infusible    Com-    parison    200    0          No shape   Fused   8.6                      retention    ______________________________________

EXAMPLE 9

Ten kinds of mixtures were prepared by mixing (1) 100 parts by weight ofNeoprene W (a tradename for a product of Showa Neoprene Co., Ltd.), 5parts by weight of zinc oxide, 4 parts by weight of highly activemagnesia, 3 parts by weight of light process oil, 1 part by weight ofstearic acid, 3 parts by weight of an accelerator (22) and 30 parts byweight of SRF black with (2) the granular or powdery resin obtained inRun No. 12 in an amount of 0, 1, 3, 5, 10, 50, 100, 150, 200, and 250parts by weight, respectively.

To each of the ten mixtures was added 2 times its amount oftrichloroethylene to dissolve it. The solution was fully stirred, andthe solvent was removed under a reduced pressure of 30 mmHg. Theresulting residue was cut to a size of 1 to 3 mm, placed in a mold (120mm×150 mm) heated in advance to 170° C., pressed while degassing, andfinally hot-pressed for 30 minutes under a pressure of 100 kg/cm² togive rubber sheets (Runs Nos. 251 to 260) shown in Table 20.

Table 20 summarizes the amount of the resin mixed; the thickness,hardness, compression set, tensile strength, tensile elongation andvolume inherent resistivity of the molded articles; and the hardness,tensile strength and tensile elongation of the molded articles afterheat-treatment at 170° C. for 24 hours.

                                      TABLE 20    __________________________________________________________________________    Amount of             Molded article               After heat-treatment    the resin        Compress-            at 170° C. for 24 hours       mixed Thick-                 Hard-                     sion Tensile                                Elon-                                    Volume                                          Hard-                                              Tensile                                                    Elon-    Run       (parts by             ness                 ness                     set  strength                                gation                                    resistivity                                          ness                                              strength                                                    gation    No.       weight)             (mm)                 (°)                     (%)  (kg/cm.sup.2)                                (%) (Ω-cm)                                          (°)                                              (kg/cm.sup.2)                                                    (%)    __________________________________________________________________________    251        0    1.1 76  16.3 73    370 6.2 × 10.sup.11                                          78  62    106    252        1    1.1 76  17.2 74    390 6.1 × 10.sup.11                                          79  55    85    253        3    1.2 79  8.9  82    260 1.1 × 10.sup.12                                          83  86    105    254        5    1.2 80  6.2  87    210 5.6 × 10.sup.12                                          87  91    93    255        10   1.3 83  5.3  105   170 1.3 × 10.sup.13                                          90  116   74    256        50   1.3 88  3.4  126   110 5.6 × 10.sup.13                                          95  144   58    257       100   1.3 90  3.0  101    80 7.8 × 10.sup.13                                          96  120   51    258       150   1.5 90  2.8  85     46 8.6 × 10.sup.13                                          97  93    22    259       200   1.7 89  3.7  31     25 2.1 × 10.sup.14                                          94  54    13    260       250   2.0 81  6.8   8     15 5.4 × 10.sup.13                                          83  11     7    __________________________________________________________________________

EXAMPLE 10

While 100 parts by weight of nitrile rubber (Hycar OR25, a tradename fora product of Japanese Zeon Co., Ltd.), 5 parts by weight of zinc oxide,1.5 parts by weight of stearic acid, 1.5 parts by weight of Altax, 3parts by weight of pine tar and 40 parts by weight of carbon black werekneaded on an open roll at 95° C., 10 parts by weight of each of theproducts of Runs Nos. 12, 44, 47, 21, 22 and 23 and wood flour wasadded. They were fully mixed and extruded into a rubber sheet. The sheetobtained was heat-treated at 170° C. under a pressure of 1 to 2 kg/cm²for 3 hours. The resulting rubber sheets so heat-treated had a thicknessof 1.0 to 1.1 mm and are designated as samples of Runs Nos. 261 to 268in the above-mentioned order of the fillers used.

Table 21 summarizes the types of the fillers used, and theirblendability, and the tensile strength and elongation of each of thesheets; and the shrinkage and tensile strength retention of the sheetsheat-treated at 180° C. for 24 hours.

                                      TABLE 21    __________________________________________________________________________                                   After heat treatment                                   at 180° C. for 24 hours                       Tensile           Strength         Type of       strength                             Elongation                                   Shrinkage                                         retention    Run No.         the filler                Blendability                       (kg/cm.sup.2)                             (%)   (%)   (%)    __________________________________________________________________________    261  None    --    73    420   4.1    95    262  Run No. 12                Very good                       97    124   1.4   156    263  Run No. 44                Very good                       91    154   1.2   168    264  Run No. 47                Very good                       93    147   1.3   165    265  Run No. 21                Fair   86    340   1.7    91    266  Run No. 22                Good   62    380   3.4   108    267  Run No. 23                Fair   84    176   2.6   113    268  Wood flour                Slightly                       55    280   3.1    75                poor    __________________________________________________________________________

EXAMPLE 11

One hundred parts by weight of each of the various rubbers shown inTable 22 was kneaded with 20 parts by weight of carbon black and thevarious compounding agents indicated in Table 24 at 50° to 110° C. usingan open roll. The kneaded mixture was extruded into a sheet form, andheat-treated at a temperature of 160° C. under a pressure of 0 to 1kg/cm² for 5 hours (16 hours in the case of fluorine rubber) to givevarious rubber sheets having a thickness of 0.9 to 1.1 mm.

Table 22 summarizes the types of the rubbers used, the types and amountsof the compounding agents, the hardness and tensile strength of each ofthe rubber sheets obtained, and the hardness, strength retention andshrinkage of each of the rubber sheets after heat-treatment at 150° C.for 24 hours.

The granular resin shown in the table was the one obtained in Run No. 35in Referential Example 2.

                                      TABLE 22    __________________________________________________________________________                 Amount                 of the                      After heat-treatment                 granular          Rubber sheet                                             at 150° C. for 24 hours                 resin                  Tensile   Strength    Run       Type of rubber                 (parts by                      Types and amounts (parts)                                   Hardness                                        strength                                             Hardness                                                  retention                                                       Shrinkage    No.       (tradename)                 weight)                      of the compounding agents                                   (°)                                        (kg/cm.sup.2)                                             (°)                                                  (%)  (%)    __________________________________________________________________________    271       Natural rubber                  0   Zinc oxide (5),                                   30   36   75    62  8.7                      stearic acid (1)    272       Natural rubber                 30   Accelerator M (1),                                   76   74   98   105  4.4                      accelerator TT (1),                      sulfur (2)    273       Nitrile rubber                  0   Zinc oxide (5),                                   61   68   67    96  2.8       (Hycar OR)     stearic acid (1),                      pine tar (3)    274       Nitrile rubber                 30   Accelerator DM (1),                                   88   66   94   153  1.4       (Hycar OR)     sulfur (2)    275       Butyl rubber                 0    Zinc oxide (5),                                   63   68   69    89  3.7       (GRI-50)       stearic acid (1),                      GMF (4)    276       Butyl rubber                 30   Lead oxide (5),                                   81   71   85   146  1.9       (GRI-50)       sulfur (1)    277       Chlorinated poly-                  0   Litharge (15), DOP (10),                                   72   61   81   102  2.4       ethylene       accelerator 22 (4)       (ELASLEN 401A)    278       Chlorinated poly-                 30   TAIC (3), perhexa                                   83   72   87   140  1.4       ethylene       3M-40 (5)       (ELASLEN 401A)    279       Chloroprene                  0   Zinc oxide (5), stearic                                   76   80   94    96  1.8       (Neoprene W)   acid (1), magnesia (4)    280       Chloroprene                 30   Light process oil (1),                                   89   78   93   121  0.4       (Neoprene W)   accelerator 22 (1)    281       Chlorosulfonated                  0   Litharge (1.5),                                   76   76   83   100  2.9       polyethylene   magnesia (10),       (Hypalon 40)   Tetron A (1)    282       Chlorosulfonated                 30   Rosin ester (2)                                   84   85   87   128  1.1       polyethylene       (Hypalon 40)    283       Fluorine rubber                  0   Magnesia (10), TET (2)                                   55   58   58   100  1.7       (VITON B)    284       Fluorine rubber                 30                78   54   81   135  0.9       (VITON B)    285       Styrene-butadiene                  0   Zinc oxide (5),                                   77   67   87    85  5.6       rubber (JSR 1502)                      stearic acid (1),                      accelerator DM (1.5),    286       Styrene-butadiene                 30   accelerator TT (1).                                   86   65   94   109  3.3       rubber (JSR 1502)                      sulfur (2)    __________________________________________________________________________

EXAMPLE 12

Ten kinds of mixtures were prepared by mixing (1) 100 parts by weight ofNeoprene W (a tradename for a product of Showa Neoprene Co., Ltd.), 5parts by weight of zinc oxide, 4 parts by weight of highly activemagnesia, 3 parts by weight of light process oil, 1 part by weight ofstearic acid, 3 parts by weight of an accelerator (22) and 30 parts byweight of SRF black with (2) the granular or powdery resin obtained inRun No. 112 in an amount of 0, 1, 3, 5, 10, 50, 100, 150, 200, and 250parts by weight, respectively.

To each of the ten mixtures was added 2 times its amount oftrichloroethylene to dissolve it. The solution was fully stirred, andthe solvent was removed under a reduced pressure of 30 mmHg. Theresulting residue was cut to a size of 1 to 3 mm, placed in a mold (120mm×150 mm) heated in advance to 170° C., pressed while degassing, andfinally hot-pressed for 30 minutes under a pressure of 100 kg/cm² togive rubber sheets (Runs Nos. 368 to 377) shown in Table 23.

Table 23 summarizes the amount of the resin mixed; the thickness,hardness, compression set, tensile strength, tensile elongation andvolume inherent resistivity of the molded articles; and the hardness,tensile strength and tensile elongation of the molded articles afterheat-treating at 200° C. for 8 hours.

                                      TABLE 23    __________________________________________________________________________    Amount of             Molded article               After heat-treatment    the resin        Compres-             at 200°  C. for 8 hours       mixed Thick-                 Hard-                     sion Tensile                                Elon-                                    Volume                                          Hard-                                              Tensile                                                    Elon-    Run       (parts by             ness                 ness                     set  strength                                gation                                    resistivity                                          ness                                              strength                                                    gation    No.       weight)             (mm)                 (°)                     (%)  (kg/cm.sup.2)                                (%) (Ω-cm)                                          (°)                                              (kg/cm.sup.2)                                                    (%)    __________________________________________________________________________    368        0    1.1 76  16.3 73    370 6.2 × 10.sup.11                                          81  48    40    369        1    1.1 76  15.9 69    360 5.8 × 10.sup.11                                          80  36    35    370        3    1.1 79  9.6  81    310 1.0 × 10.sup.12                                          84  83    75    371        5    1.1 80  7.1  84    280 7.8 × 10.sup.12                                          86  87    90    372        10   1.2 82  4.8  101   220 1.9 × 10.sup.13                                          88  107   125    373        50   1.3 85  3.3  118   160 3.7 × 10.sup.13                                          90  132   110    374       100   1.3 88  2.6  105   130 4.8 × 10.sup.13                                          92  111   85    375       150   1.4 89  2.6  82     65 7.4 × 10.sup.13                                          95  96    40    376       200   1.5 89  3.9  47     30 9.6 × 10.sup.13                                          94  51    25    377       250   1.8 78  7.4  11     20 6.7 × 10.sup.13                                          87  15    10    __________________________________________________________________________

EXAMPLE 13

While 100 parts by weight of nitrile rubber (Hycar OR25, a tradename fora product of Japanese Zeon Co., Ltd.), 5 parts by weight of zinc oxide,1.5 parts by weight of stearic acid, 1.5 parts by weight of Altax, 3parts by weight of pine par, 1 part by weight of an accelerator (DM) and2 parts by weight of sulfur, and 40 parts by weight of carbon black werekneaded on an open roll at 95° C., 40 parts by weight of each of theproducts of Runs Nos. 113, 134, 140, 147, 150, 163, 167, 21, 22 and 23and wood flour was added as a filler. They were fully mixed and extrudedinto a rubber sheet. The sheet obtained was heat-treated at 170° C.under a pressure of 1 to 2 kg/cm² for 3 hours. The resulting rubbersheets so heat-treated had a thickness of 1.0 to 1.2 mm and aredesignated as samples of Runs Nos. 379 to 389 in the order of thefillers used, and Run No. 379 in which no filler was used.

Table 24 summarizes the types of the fillers used, and theirblendability, and the tensile strength and elongation of each of thesheets; and the shrinkage and tensile strength retention of the sheetsheat-treated at 180° C. for 24 hours.

                                      TABLE 24    __________________________________________________________________________                                   After heat-treatment                         Tensile                               Elon-                                   at 180° C. for 24 hours    Run            Blend-                         strength                               gation                                   Shrinkage                                         Strength re-    No.       Type of the filler                   ability                         (kg/cm.sup.2)                               (%) (%)   tention (%)    __________________________________________________________________________    378       None         --   73    420 4.1    95    379       Product of Run No. 113                   Very good                         86    175 1.6   141    380       Product of Run No. 134                   Very good                         105   140 1.3   165    381       Product of Run No. 140                   Very good                         87    180 1.7   146    382       Product of Run No. 147                   Very good                         93    190 1.7   151    383       Product of Run No. 150                   Very good                         84    170 1.5   146    384       Product of Run No. 163                   Very good                         112   130 1.1   160    385       Product of Run No. 167                   Very good                         108   105 1.2   174    386       Powder of Run No. 21                   Fair  86    340 1.7    91    387       Product of Run No. 22                   Good  62    380 3.4   108    388       Powder of Run No. 23                   Fair  84    176 2.6   113    389       Wood flour  Slightly                         55    280 3.1    75                   poor    __________________________________________________________________________

EXAMPLE 14

One hundred parts by weight of each of the various rubbers shown inTable 25 was kneaded with 20 parts by weight of carbon black and thevarious compounding agents indicated in Table 25 at 50° to 110° C. usingan open roll. The kneaded mixture was extruded into a sheet form, andheat-treated at a temperature of 160° C. under a pressure of 0 to 2kg/cm² for 5 hours (16 hours in the case of fluorine rubber) to givevarious rubber sheets having a thickness of 0.9 to 1.2 mm.

Table 25 summarizes the types of the rubbers used, the types and amountsof the compounding agents, the hardness and tensile strength of each ofthe rubber sheets obtained, and the hardness, strength retention andshrinkage of each of the rubber sheets after heat-treatment at 150° C.for 24 hours.

The granular resin shown in the table was the one obtained in Run No.164 in Referential Example 8.

                                      TABLE 25    __________________________________________________________________________                 Amount                 of the                      After heat-treatment                 granular          Rubber sheet                                             at 150° C. for 24 hours                 resin                  Tensile   Strength    Run       Type of rubber                 (parts by                      Types and amounts (parts)                                   Hardness                                        strength                                             Hardness                                                  retention                                                       Shrinkage    No.       (tradename)                 weight)                      of the compounding agents                                   (°)                                        (kg/cm.sup.2)                                             (°)                                                  (%)  (%)    __________________________________________________________________________    390       Natural rubber                  0   Zinc oxide (5),                                   30   36   75    62  8.7                      stearic acid (1),    391       Natural rubber                 30   accelerator M (1),                                   71   87   94   113  4.6                      accelerator TT (1),                      sulfur (2)    392       Nitrile rubber                  0   Zinc oxide (5),                                   61   68   67    96  2.8       (Hycar OR)     stearic acid (1).                      pine tar (3)    393       Nitrile rubber                 30   accelerator DM (1),                                   84   79   91   147  1.3       (Hycar OR)     sulfur (2)    394       Butyl rubber                  0   Zinc oxide (5),                                   63   68   69    89  3.7       (GRI-50)       stearic acid (1),                      GMF (4),    395       Butyl rubber                 30   lead oxide (5),                                   77   85   84   133  1.6       (GRI-50)       sulfur (1)    396       Chlorinated                  0   Litharge (15).                                   72   61   81   102  2.4       polyethylene   DOP (10),       (ELASLEN 401A) accelerator 22 (4),    397       Chlorinated                 30   TAIC (3).    80   92   82   155  1.2       polyethylene   perhexa 3M-40 (5)       (ELASLEN 401A)    398       Chloroprene                  0   Zinc oxide (5),                                   76   80   94    96  1.8       (Neoprene W)   stearic acid (1).                      magnesia (4),    399       Chloroprene                 30   light process oil (1),                                   83   96   89   136  0.6       (Neoprene W)   accelerator 22 (1)    400       Chlorosulfonated                  0   Litharge (1.5)                                   76   76   83   100  2.9       polyethylene   magnesia (10),       (Hypalon 40)   Tetron A (1),    401       Chlorosulfonated                 30   rosin ester (2)                                   80   102  86   147  1.3       polyethylene       (Hypalon 40)    402       Fluorine rubber                  0   Magnesia (10),                                   55   58   58   100  1.7       (Viton B)      TET (2)    403       Fluorine rubber                 30                73   76   79   154  0.9       (Viton B)    404       Styrene-   0   Zinc oxide (5),                                   77   67   87    85  5.6       butadiene      stearic acid (1),       rubber         accelerator TT (1),       (JSR 1502)     sulfur (2)    405       Styrene-  30                81   80   91   120  2.5       butadiene       rubber       (JSR 1502)    __________________________________________________________________________

EXAMPLE 15

Sixty parts by weight of the product of Run No. 43 (as a matrix) wasmixed with 40 parts by weight of each of glass staples (Run No. 551) cutto a size of 3 mm, rock wool (Run No. 552), carbon black (Run No. 553),hollow microspheres (Run No. 554), wood flour (Run No. 555), kraft pulp(Run No. 556) and 6-nylon staples (Run No. 557) cut to a size of 3 mm. Apredetermined amount of the mixture was put in a mold heated to atemperature of 120° C. using a press and treated under a pressure of 300kg/cm° for 30 minutes to give ten molded test pieces having a width of12 mm, a length of 100 and a thickness of 4.8 to 5.1 mm in each Run.Similarly, ten molded test pieces were prepared under the sameconditions as above using 60 parts by weight of the product of Run No.47 (as a matrix) and 47 parts by weight of the glass staples (Run No.558) and wood flour (Run No. 559). For comparison, 60 parts by weight,as solids, of the uncured resol resin used in Run No. 21 (as a matrix)as a solution was mixed with 40 parts by weight of each of glass staples(Run No. 560) cut to 3 mm, rock wool (Run No. 561), carbon black (RunNo. 562), hollow microspheres (Run No. 563), wood flour (Run No. 564),kraft pulp (Run No. 565) and 6-nylon staples cut to 3 mm (Run No. 566).The mixture was dried in the air at room temperature for 24 hours, andthen dried at 80° C. for 30 minutes to remove the solvent. Apredetermined amount of the resulting mixture was treated under apressure of 300 kg/cm² for 30 mimutes in a mold heated in advance to150° C. using a press to give ten molded test samples each having awidth of 12 mm, a length of 100 mm and a thickness of 3.0 to 3.2 mm ineach run.

Table 26 shows the types of the matrices and fillers used, the averageflexural strength of five molded samples, and the heat-resistanttemperatures of the molded samples.

                  TABLE 26    ______________________________________                                          Heat-                                 Flexural resistant    Run  Type of     Type of     strength tempera-    No.  the matrix  the filler  (kg/cm.sup.2)                                          ture (°C.)    ______________________________________    551  Product of  Glass staples                                 880      210         Run No. 43    552  Product of  Asbestos    670      190         Run No. 43    553  Product of  Carbon black                                 520      220         Run No. 43    554  Product of  Hollow      510      210         Run No. 43  microspheres    555  Product of  Wood flour  460      170         Run No. 43    556  Product of  Kraft pulp  650      170         Run No. 43    557  Product of  6-Nylon staples                                 770      150         Run No. 43    558  Product of  Glass staples                                 830      210         Run No. 47    559  Product of  Wood flour  470      170         Run No. 47    560  Resol resin Glass staples                                 650      180         of Run No. 21    561  Resol resin Asbestos    460      160         of Run No. 21    562  Resol resin Carbon black                                 440      180         of Run No. 21    563  Resol resin Hollow      290      190         of Run No. 21                     microspheres    564  Resol resin Wood flour  320      150         of Run No. 21    565  Resol resin Kraft pulp  470      140         of Run No. 21    566  Resol resin 6-Nylon staples                                 570      120         of Run No. 21    ______________________________________

In Runs Nos. 551 to 559, molding could be performed without any trouble,but in Runs Nos. 560 to 566, the flow of the resin was poor and muchgases were generated, thus showing poor moldability.

EXAMPLE 16

In accordance with the method of Example 15, 30 parts by weight of theproduct of Run No. 12 (as a filler), 25 parts by weight of glass staplescut to a size of 2 mm (as a filler) and 45 parts by weight of each ofthe uncured resol resin used in Run No. 21, the novolak resin used inRun No. 22 (containing 15 parts by weight of hexamine), a furan resin(Hitafuran 303, a tradename for a product of Hitachi Chemical, Limited),an epoxy resin (Epikote 815, a tradename for a product of Shell ChemicalCo.) and a melamine resin (MERUMAITE, a tradename for a product of ToyoKoatsu Co., Ltd.) as a matrix (Runs Nos. 571 to 575 in this order ofmatrices) were mixed in the form of a powder or solution. Apredetermined amount of each of the resulting mixtures was molded at atemperature of 150° to 70° C. under a pressure of 200 to 400 kg/cm² for30 minutes using a hot press and a mold in accordance with Example 1 togive five test samples for measurement of compression strength eachhaving a width of 10 mm, a length of 10 mm and a thickness of 3.5 to 3.6mm and five test samples for measurement of heat conductivity eachhaving a width of 100 mm, a length of 100 mm and a thickness of 4.9 to5.1 mm.

As controls, test samples were prepared in the same way as above using55 parts by weight of glass fibers cut to a length of 2 mm, and 45 partsby weight of each of the uncured resol resin used in Run No. 21, thenovolak resin used in Run No. 22 (containing 15 parts by weight ofhexamethylenetetramine), the furan resin, the epoxy resin and themelamine resin (Runs Nos. 576 to 580).

Table 27 summarizes the types and amounts of the fillers used, the typesof the matrices (45 parts by weight), and the average compressionstrength and heat conductivity values of the molded articles.

                                      TABLE 27    __________________________________________________________________________     Filler    (parts by weight)                   Matrix resin                           Compression                                  Heat         Product of               Glass                   (45 parts                           strength                                  conductivity    Run No.         Run No. 12               fibers                   by weight)                           (kg/cm.sup.2)                                  (cal/cm · sec · °C.                                  )    __________________________________________________________________________    571  30    26  Resol resin                           2,430   5.7 × 10.sup.-4    572  30    25  Novolak resin                           2,040   6.2 × 10.sup.-4    573  30    25  Furan resin                           1,720   6.8 × 10.sup.-4    574  30    25  Epoxy resin                           1,530   6.5 × 10.sup.-4    575  30    252 Melamine resin                           1,460   9.1 × 10.sup.-4    576  Not used               55  Resol resin                           1,780  10.4 × 10.sup.-4    577  Not used               55  Novolak resin                           1,270  10.8 × 10.sup.-4    578  Not used               55  Furan resin                           1,040  10.9 × 10.sup.-4    579  Not used               55  Epoxy resin                           1,150  11.1 × 10.sup.-4    580  Not used               55  Melamine resin                             940  14.6 × 10.sup.-4    __________________________________________________________________________

As in Runs Nos. 576 to 580, an attempt was made to obtain a moldedparticle by using 25 parts by weight of glass fibers and 75 parts byweight of each of the matrix resins without the product of Run No. 12.But the moldability was poor and molded articles of satisfactory qualitycould not be obtained.

EXAMPLE 17

The uncured resol resin solution used in Run No. 21 was mixed with theproduct of Run No. 35 as a filler in various proportions. The mixtureswere each dried in the air at room temperature for 48 hours, and furthertreated at 70° C. for 60 minutes. A molding mixture was prepared in thesame way as above from the aforesaid resol resin solution and each ofthe powders obtained in Runs Nos. 21 and 22.

Each of the mixtures was molded at a temperature of 150° to 180° C.under a pressure of 200 kg/cm² to prepare 15 test samples having a widthof 12 mm, a length of 100 mm and a thickness of 3.0 to 3.5 mm in eachrun.

Table 28 summarizes the amounts of the resol resin (solids), the productof Run No. 35 and the powders of Runs Nos. 21 and 22, the moldability ofeach of the mixtures, and the heat resistant temperatures and volumeresistivities of the molded articles.

                                      TABLE 28    __________________________________________________________________________                                 Molded article               Filler            Heat         Resol resin Amount      resistant                                      Volume         (parts by   (parts by   tempera-                                      resistivity    Run No.         weight)               Type  weight)                          Moldability                                 ture (°C.)                                      (ohm-cm)    __________________________________________________________________________    581  100   Product of                      0   Very difficult                                 150  10.sup.13               Run No. 35    582  85    Product of                     15   Good   180  10.sup.14               Run No. 35    583  75    Product of                     25   Very good                                 210  10.sup.14               Run No. 35    584  65    Product of                     35   Very good                                 230  10.sup.14               Run No. 35    585  50    Product of                     50   Very good                                 240  10.sup.14               Run No. 35    586  50    Powder of                     50   Difficult                                 160  10.sup.11               Run No. 21    587  50    Powder of                     50   Good   140  10.sup.12               Run No. 22    __________________________________________________________________________

EXAMPLE 18

Sixty parts by weight of the product of Run No. 135 (as a matrix) wasmixed with 40 parts by weight of each of glass staples (Run No. 671) cutto a size of 3 mm, rock wool (Run No. 672), carbon black (Run No. 673),hollow microspheres (Run No. 674), wood flour (Run No. 675), kraft pulp(Run No. 676), 6-nylon staples (Run No. 677) cut to a size of 3 mm, andKevlar staples (Run No. 678) cut to a size of 3 mm. A predeterminedamount of the mixture was put in a mold hated to a temperature of 120°C. using a press and treated under a pressure of 250 to 350 kg/cm² for30 minutes to give ten molded test pieces having a width of 12 mm, alength of 100 mm and a thickness of 3.5 to 3.8 mm in each run.Similarly, ten molded test samples were prepared under the sameconditions as above from each of mixtures prepared from 60 parts byweight of the product of Run No. 163 (as a matrix) and 40 parts byweight of the glass staples (Run No. 679), the wood flour (Run No. 680)and the 6-nylon staples (Run No. 681), respectively, and mixturesprepared from 60 parts by weight of the product of Run No. 167 (as amatrix) and 40 parts by weight of the glass staples (Run No. 682), thewood flour (Run No. 683) and the 6-nylon staples (Run No. 684),respectively.

For comparison, 60 parts by weight of the uncured resol resin (as amatrix) used in Run No. 21 as a solution was mixed with 40 parts byweight of each of glass staples (Run No. 685) cut to a size of 3 mm,rock wool (Run No. 686), carbon black (Run No. 687), hollow microspheres(Run No. 688), wood flour (Run No. 689), kraft pulp (Run No. 690),6-nylon staples (Run No. 691) cut to a size of 3 mm and Kevlar staples(Run No. 692) cut to a size of 3 mm. The mixture was dried in the air atroom temperature for 24 hours, and then dried at 80° C. for 30 minutesto remove the solvent. A predetermined amount of the resulting mixturewas treated under a pressure of 250 to 350 kg/cm² for 30 minutes in amold heated in advance to 150° C. using a press to give ten molded testsamples each having a width of 12 mm, a length of 100 mm and a thicknessof 3.0 to 3.2 mm in each run.

Table 29 shows the types of the matrices and fillers used, the averageflexural strength of five molded samples, and the heat-resistanttemperatures of the five molded samples.

                  TABLE 29    ______________________________________                                          Heat-                                 Flexural resistant    Run  Type of     Type of     strength tempera-    No.  the matrix  the filler  (kg/cm.sup.2)                                          ture (°C.)    ______________________________________    671  Product of  Glass staples                                 1.030    220         Run No. 135    672  Product of  Rock wool   780      190         Run No. 135    673  Product of  Carbon black                                 640      230         Run No. 135    674  Product of  Hollow      600      220         Run No. 135 microspheres    675  Product of  Wood flour  510      170         Run No. 135    676  Product of  Kraft pulp  690      180         Run No. 135    677  Product of  6-Nylon staples                                 870      170         Run No. 135    678  Product of  Glass staples                                 1,210    200         Run No. 135    679  Product of  Kelvar fibers                                 1.140    230         Run No. 163    680  Product of  Wood flour  630      170         Run No. 163    681  Product of  6-Nylon staples                                 770      180         Run No. 163    682  Product of  Glass staples                                 1,090    220         Run No. 167    683  Product of  Wood flour  540      180         Run No. 167    684  Product of  6-Nylon staples                                 810      160         Run No. 167    685  Resol resin Glass staples                                 650      180         of Run No. 21    686  Resol resin Rock wool   460      160         of Run No. 21    687  Resol resin Carbon black                                 440      180         of Run No. 21    688  Resol resin Hollow      290      190         of Run No. 21                     microspheres    689  Resol resin Wood flour  320      150         of Run No. 21    690  Resol resin Kraft pulp  470      140         of Run No. 21    691  Resol resin 6-Nylon staples                                 570      120         of Run No. 21    692  Resol Resin Kelvar fibers                                 780      120         of Run No. 21    ______________________________________

In Runs Nos. 671 to 684, molding could be performed easily without anytrouble. But in Runs Nos. 685 to 692, the flow of the resin compositionwas poor, or the resol resin molded away from the mold. Furthermore,much gases were generated to degrade moldability.

EXAMPLE 19

In accordance with the method of Example 18, 30 parts by weight of theproduct of Run No. 140 (as a filler), 25 parts by weight of glassstaples cut to a size of 2 mm (as a filler) and 45 parts by weight ofeach of the uncured resol resin used in Run No. 21, the novolak resinused in Run No. 22 (containing 15 parts by weight of hexamine), a furanresin (Hitafuran 303, a tradename for a product of Hitachi Chemical,Limited), an epoxy resin (Epikote 815, a tradename for a product ofShell Chemical Co.) and a melamine resin (MERVMAITE, a tradename for aproduct of Toyo Koatsu Co., Ltd.) as a matrix (Runs Nos. 693 to 697 inthis order of matrices) were mixed in the form of a powder or solution.A predetermined amount of each of the resulting mixtures was molded at atemperature of 150° to 170° C. under a pressure of 200 to 400 kg/cm² for30 minutes using a hot press and a mold in accordance with Example 18 togive five test samples for measurement of compression strength eachhaving a width of 10 mm, a length of 10 mm and a thickness of 3.3 to 3.7mm and five test samples for measurement of heat conductivity eachhaving a width of 100 mm, a length of 100 mm and a thickness of 4.7 to5.1 mm. Similarly, test samples were prepared as above using the productof Run No. 147 (as a filler and the product of Run No. 150 (as a filler)(Runs Nos. 698 to 707).

As controls, test samples were prepared in the same way as above using55 parts by weight of glass fibers cut to a length of 2 mm, and 45 partsby weight of each of the uncured resol used in Run No. 21, the novolakresin used in Run No. 22 (containing 15 parts by weight ofhexamethylenetetramine), the furan resin, the epoxy resin and themelamine resin (Runs Nos. 708 to 712).

Table 30 summarizes the types and amounts of the fillers used, the typesof the matrices (45 parts by weight), and the average compressionstrength and heat conductivity values of the molded articles.

                  TABLE 30    ______________________________________    Filler    (parts by weight)         Type of the        Type of the                                    Compres-                                           Heat con-         filler             matrix  sion   ductivity    Run  (30 parts  Glass   (45 parts                                    strength                                           (cal/cm ·    No.  by weight) fibers  by weight)                                    (kg/cm.sup.2)                                           sec · °C.)    ______________________________________    693  Product of 25      Resol resin                                    2,640  6.1 × 10.sup.-4         Run No. 140    694  Product of 25      Novolak 2,050  6.9 × 10.sup.-4         Run No. 140        resin    695  Product of 25      Furan resin                                    1,920  7.6 × 10.sup.-4         Run No. 140    696  Product of 25      Epoxy resin                                    1,680  7.2 × 10.sup.-4         Run No. 140    697  Product of 25      Melamine                                    1,590 10.3 × 10.sup.-4         Run No. 140        resin    698  Product of 25      Resol resin                                    2,210  7.4 × 10.sup.-4         Run No. 147    699  Product of 25      Novolak 1,870  6.9 × 10.sup.-4         Run No. 147        resin    700  Product of 25      Furan resin                                    1,550  8.6 × 10.sup.-4         Run No. 147    701  Product of 25      Epoxy   1,440  8.5 × 10.sup.-4         Run No. 147        resin    702  Product of 25      Melamine                                    1.230 11.3 × 10.sup.-4         Run No. 147        resin    703  Product of 25      Resol resin                                    2,390  5.4 × 10.sup.-4         Run No. 150    704  Product of 25      Novolak 2,110  6.7 × 10.sup.-4         Run No. 150        resin    705  Product of 25      Furan resin                                    1,860  7.4 × 10.sup.-4         Run No. 150    706  Product of 25      Epoxy   1,540  6.8 × 10.sup.-4         Run No. 150        resin    707  Product of 25      Melamine                                    1,470  9.7 × 10.sup.-4         Run No. 150        resin    708  Not used   55      Resol resin                                    1,780 10.4 × 10.sup.-4    709  Not used   55      Novolak 1,270 10.8 ×  10.sup.-4                            resin    710  Not used   55      Furan resin                                    1,040 10.9 × 10.sup.-4    711  Not used   55      Epoxy   1,150 11.1 × 10.sup.-4                            resin    712  Not used   55      Melamine                                      940 14.6 × 10.sup.-4                            resin    ______________________________________

As in Runs Nos. 708 to 712, an attempt was made to obtain moldedarticles by using 25 parts by weight of glass staples and 75 parts byweight of each of the matrix resins without the product of Run No. 140,or the product of Run No. 147 or the product of Run No. 150. But thematrix resin flowed out from the mold or foamed, so that molded articlesof satisfactory quality could not be obtained.

EXAMPLE 20

The uncured resol resin solution used in Run No. 21 was mixed with theproduct of Run No. 112 as a filler in various proportions. Each of themixtures was dried in the air at room temperature for 48 hours, andfurther treated at 70° C. for 60 minutes. Molding mixtures were preparedin the same way as above from the aforesaid resol resin solution and thepowders of Runs Nos. 21 and 22 as fillers.

Each of the molding mixtures obtained was molded at 150° to 180° C. and200 kg/cm² using a press and a mold to give 15 test samples each havinga width of 12 mm, a length of 100 mm and a thickness of 3.0 to 3.5 mm ineach run.

Table 31 summarizes the amounts of the resol resin (solids), the productof Run No. 112, the powder of Run No. 21 and the powder of Run No. 22,the moldability of each of the molding mixtures, and the heat resistanttemperatures and volume resistivities before or after boiling of theresulting molded products.

                                      TABLE 31    __________________________________________________________________________                                 Molded article                                      Volume    Resol     Filler             Heat resistivity    resin            Amount      resistant                                      (ohm-cm)         (parts by   (parts by   tempera-                                      Before                                          After    Run No.         weight)              Type   weight)                          Moldability                                 ture (°C.)                                      boiling                                          boiling    __________________________________________________________________________    713  100  Product of                      0   Very difficult                                 150  10.sup.14                                          10.sup.5              resin No. 112    714  85   Product of                     15   Good   180  10.sup.14                                          10.sup.12              resin No. 112    715  75   Product of                     25   Very Good                                 220  10.sup.14                                          10.sup.13              resin No. 112    716  65   Product of                     35   "      240  10.sup.14                                          10.sup.14              resin No. 112    717  50   Product of                     50   "      250  10.sup.13                                          10.sup.13              resin No. 112    718  40   Product of                     60   "      250  10.sup.13                                          10.sup.13              resin No. 112    719  50   Powder of                     50   Difficult                                 160  10.sup.14                                          10.sup.8              Run No. 21    720  50   Powder of                     50   Good   140  10.sup.13                                          10.sup.9              Run No. 22    __________________________________________________________________________

The test samples obtained in Runs Nos. 713, 719 and 720 showed traces offoaming and surface roughness.

EXAMPLE 21

Forty parts by weight of the uncured novolak resin used in Run No. 22(as a filler) was mixed in powder form with 60 parts by weight of eachof the product of Run No. 113, the product of Run No. 167, the productof Run No. 21, the powder of Run No. 22 and the powder of Run No. 23.Each of the mixtures was put in methanol heated in advance to 160° C.,extruded from a nozzle having a diameter of 1 mm under a pressure of 5kg/cm² and received in a square mold each side measuring 50 mm andhaving a depth of 25 mm. The resulting plate-like article was cooled toroom temperature and then withdrawn from the mold.

Table 32 summarizes the extrusion moldability of each of the mixtures,the apparent thickness and bulk density of each of the plate-likearticles extruded from the nozzle, and the shape of each plate-likearticle when it was heated to a temperature of 200° C. at a rate of 25°C./hour in a desiccator.

                                      TABLE 32    __________________________________________________________________________                           Plate-like article                           Apparent                               Bulk                                   Shape upon    Run            Extrusion                           thickness                               density                                   heat-treatment    No.       Type of the filler                   moldability                           (mm)                               (g/cc)                                   at 200° C.    __________________________________________________________________________    721       Product of Run No. 113                   Very good                           24-25                               0.3-0.4                                   Partly melted                                   shape retained.    722       Product of Run No. 167                   Very good                           24-25                               0.4-0.5                                   Infusible;                                   shape retained.    723       Powder of Run No. 21                   The nozzle was                           12-13                               0.7-0.8                                   Melted                   blocked up                   gradually.    724       Powder of Run No. 22                   The nozzle was                           19-20                               0.6-0.7                                   Melted                   blocked up                   gradually.    725       Powder of Run No. 23                   The nozzle was                           2-3 0.9-1.0                                   Melted                   blocked up                   within a short                   period of time.    __________________________________________________________________________

In the plate-like articles obtained in Runs Nos. 721 and 722, the fillerand the matrix were present in the uniformly mixed state. On the otherhand, in Runs Nos. 723 to 725, the proportion of the matrix increased asthe time passed after the extrusion of the articles from the nozzle.

What is claimed is:
 1. A resin composition comprising(I) a granular orpowdery resin which is a condensation product of a phenol, and analdehyde and wherein (A) at least 30% of the granular or powder resinconsists of spherical primary particles and their secondary agglomeratedparticles each having a particle diameter of 0.1 to 150 microns, (B)said granular or powdery resin has such a size that at least 50% byweight thereof can pass through a 100 Tyler mesh sieve, and (C) saidgranular or powdery resin has a free phenol content, determined byliquid chromatography, of not more than 500 ppm, and (II) a fillermaterial other than said granular or powdery resin (I).
 2. Thecomposition of claim 1 wherein the granular or powdery resin is acondensation product of a phenol and an aldehyde, and has a D₉₉₀₋₁₀₁₅/D₁₆₀₀ ratio of from 0.2 to 9.0 and D₈₉₀ /D₁₆₀₀ ratio of from 0.09 to1.0 in its infrared absorption spectrum measured by a KBr tablet method,in which D₁₆₀₀ represents the absorption intensity of an absorption peakat 1600 cm⁻¹, D₉₉₀₋₁₀₁₅ represents the highest absorption intensity ofabsorption peaks in the range of 990 to 1015 cm⁻¹, and D₈₉₀ representsthe absorption intensity of an absorption peak at 890 cm⁻¹.
 3. Thecomposition of claim 2 wherein at least 70% by weight of the granular orpowdery resin has a size that can pass through a 100 Tyler mesh sieve.4. The composition of claim 1 wherein the granular or powdery resin is anitrogen-containing condensation product of a phenol, an aldehyde and anitrogen-containing compound having at least two active hydrogen, andhas a D₉₆₀₋₁₀₂₀ /D₁₄₅₀₋₁₅₀₀ ratio of from 0.1 to 2.0 in its infraredabsorption spectrum measured by a KBr tablet method in which D₁₄₅₀₋₁₅₀represents the highest absorption intensity of absorption peaks in therange of 1450 to 1500 cm⁻¹, and D₉₆₀₋₁₀₂₀ represents the highestabsorption intensity of absorption peaks in the range of 960 to 1020cm⁻¹.
 5. The composition of claim 4 wherein at least 30% of the granularor powdery resin consists of spherical primary particles and theirsecondary agglomerated particles each having a particle diameter of 0.1to 100 microns.
 6. The composition of claim 5 wherein at least 70% byweight of the granular or powdery resin has a size that can pass througha 150 Tyler mesh sieve.
 7. The composition of claim 4 wherein thegranular or powdery resin has a D₁₂₈₀₋₁₃₆₀ /D₁₄₅₀₋₁₅₀₀ ratio of from0.15 to 3.0 in its infrared absorption spectrum measured by a KBr tabletmethod in which D₁₂₈₀₋₁₃₆₀ represents the highest absorption intensityof absorption peaks in the range of 1280 to 1360 cm⁻¹, and D₁₄₅₀₋₁₅₀₀represents the highest absorption intensity of absorption peaks in therange of 1450 to 1500 cm⁻¹.
 8. The composition of claim 1 wherein thegranular or powdery resin is at least partly fused when maintained at100° C. for 5 minutes in accordance with the heat fusibility testdescribed in the specification.
 9. The composition of claim 1 whereinthe granular or powdery resin has a methanol solubility, S defined bythe following equation, of at least 20% by weight

    S=[(W.sub.o -W.sub.1)/W.sub.o ]×100(%)

wherein W_(o) is the weight in grams of the resin, and W₁ is the weightin grams of the resin left after heating under reflux, when about 10 gof the resin is heated under reflux in 500 ml of substantially anhydrousmaterial.
 10. The composition of claim 1 wherein the filler material isan inorganic substance.
 11. The composition of claim 10 wherein thefiller material is glass fibers, carbon fibers or rock wool.
 12. Thecomposition of claim 10 wherein the filler material is carbon, silica,alumina, silica-alumina, diatomaceous earth, calcium carbonate, calciumsilicate, magnesium oxide, clay, antimony oxide or hollow microspheres.13. The composition of claim 1 wherein the filler material is an organicmaterial.
 14. The composition of claim 13 wherein the organic fillermaterial is wood flour, linter, pulp or polyamide fibers.
 15. Thecomposition of claim 1 wherein the proportion of the filler material is5 to 89% by weight based on the total weight of it and the granular orpowdery resin (I).